Intercellular signaling regulates a variety of important biological functions. For example, transforming growth factor type beta (TGF-β) regulates the proliferation and differentiation of a variety of cell types binding to and activating cell surface receptors which possess serine-threonine kinase activity. Atfi et al. (Proc. Natl. Acad. Sci. U.S.A. 92, 12110–04, 1995) have shown that TGF-β activates a 78-kDa protein (p78) serine/threonine kinase; the p78 kinase was activated only in cells for which TGF-β acts as a growth inhibitory factor. Because of the important functions of kinases such as p78, there is a need in the art to identify new kinases and methods of regulating these new kinases for therapeutic effects.
It is an object of the invention to provide reagents and methods of regulating a human serine/threonine kinase. This and other objects of the invention are provided by one or more of the embodiments described below.
The invention relates to an isolated polynucleotide from the group consisting of:    a) a polynucleotide encoding a Serine/threonine kinase polypeptide comprising an amino acid sequence selected from the group consisting of:            amino acid sequences which are at least about 89% identical to        the amino acid sequence shown in SEQ ID NO: 2; and        the amino acid sequence shown in SEQ ID NO: 2.            b) a polynucleotide comprising the sequence of SEQ ID NO: 1;    c) a polynucleotide which hybridizes under stringent conditions to a poly-nucleotide specified in (a) and (b) and encodes a Serine/threonine kinase polypeptide;    d) a polynucleotide the sequence of which deviates from the polynucleotide sequences specified in (a) to (c) due to the degeneration of the genetic code and encodes a Serine/threonine kinase polypeptide; and    e) a polynucleotide which represents a fragment, derivative or allelic variation of a polynucleotide sequence specified in (a) to (d) and encodes a Serine/threonine kinase polypeptide.
A novel human serine/threonine kinase is a discovery of the present invention. Human serine/threonine kinase comprises the amino acid sequence shown m SEQ ID NO: 2. A coding sequence for human serine/threonine kinase is shown in SEQ ID NO: 1. This sequence is located on chromosome 1q42. A homologues sequence from rat (rattus norvegicus) is shown in SEQ ID NO: 3. Related ESTs (SEQ ID NOS: 4–20) are expressed in prostate (adenocarcinoma, cell line), liver (adenocarcinoma, cell line), eye (retinoblastoma), pancreas (islets of Langerhans), brain (anaplastic oligodendroglioma, schizophrenic brain S-11 frontal lobe), placenta, melanocytes, and uterus (serous papillary carcinoma, high grade).
The protein kinase domain, a phorbol ester/diacylglycerol binding domain, protein kinase C terminal domain, PH domain, and CNH domain are found. The 3D structure infers LBRI 481 to a cAMP-dependent protein kinase (catalytic subunit).
Furthermore, ATP-binding region, kinase active site. Active site D residue and sites of ATP-binding, and NP-binding are also found in SEQ ID NO: 2.
Human serine/threonine kinase of the invention is expected to be useful for the same purposes as previously identified serine/threonine kinases. Human serine/threonine kinase is believed to be useful in therapeutic methods to treat disorders such as cancer, diabetes, neurological disorders, cardiovascular disorders, musculo-skeletal disorders, inflammatory disorders, genitourological disorders, and respiratory disorders (e.g., asthma and COPD). Human serine/threonine kinase also can be used to screen for human serine/threonine kinase activators and inhibitors.
One embodiment of the present invention is an expression vector containing any polynucleotide of the present invention.
Yet another embodiment of the present invention is a host cell containing any expression vector of the present invention.
Still another embodiment of the present invention is a substantially purified Serine/threonine kinase polypeptide encoded by any polynucleotide of the present invention.
Even another embodiment of the present invention is a method of producing a Serine/threonine kinase polypeptide of the present invention, wherein the method comprises the following steps:    a. culturing the host cells of the present invention under conditions suitable for the expression of the Serine/threonine kinase polypeptide; and    b. recovering the Serine/threonine kinase polypeptide from the host cell culture.
Yet another embodiment of the present invention is a method for detecting a polynucleotide encoding a Serine/threonine kinase polypeptide in a biological sample comprising the following steps:    a. hybridizing any polynucleotide of the present invention to a nucleic acid material of a biological sample, thereby forming a hybridization complex; and    b. detecting said hybridization complex.
Still another embodiment of the present invention is a method for detecting a polynucleotide of the present invention or a Serine/threonine kinase polypeptide of the present invention comprising the steps of:    a. contacting a biological sample with a reagent which specifically interacts with the polynucleotide or the Serine/threonine kinase polypeptide and    b. detecting the interaction
Even another embodiment of the present invention is a diagnostic kit for conducting any method of the present invention.
Yet another embodiment of the present invention is a method of screening for agents which decrease the activity of a Serine/threonine kinase, comprising the steps of:    a. contacting a test compound with a Serine/threonine kinase polypeptide encoded by any polynucleotide of the present invention;    b. detecting binding of the test compound to the Serine/threonine kinase polypeptide, wherein a test compound which binds to the polypeptide is identified as a potential therapeutic agent for decreasing the activity of a Serine/threonine kinase.
Still another embodiment of the present invention is a method of screening for agents which regulate the activity of a Serine/threonine kinase, comprising the steps of:    a. contacting a test compound with a Serine/threonine kinase polypeptide encoded by any polynucleotide of the present invention; and    b. detecting a Serine/threonine kinase activity of the polypeptide, wherein a test compound which increases the Serine/threonine kinase activity is identified as a potential therapeutic agent for increasing the activity of the Serine/threonine kinase, and wherein a test compound which decreases the Serine/threonine, kinase activity of the polypeptide is identified as a potential therapeutic agent for decreasing the activity of the Serine/threonine kinase.
Even another embodiment of the present invention is a method of screening for agents which decrease the activity of a Serine/threonine kinase, comprising the step of:
contacting a test compound with any polynucleotide of the present invention and detecting binding of the test compound to the polynucleotide, wherein a test compound which binds to the polynucleotide is identified as a potential therapeutic agent for decreasing the activity of Serine/threonine kinase.
Yet another embodiment of the present invention is a method of reducing the activity of a Serine/threonine kinase, comprising the step of:
contacting a cell with a reagent which specifically binds to any polynucleotide of the present invention or any Serine/threonine kinase polypeptide of the present invention, whereby the activity of Serine/threonine kinase is reduced.
Still another embodiment of the present invention is a reagent that modulates the activity of a Serine/threonine kinase polypeptide or a polynucleotide wherein said reagent is identified by any methods of the present invention.
Even another embodiment of the present invention is a pharmaceutical composition, comprising:
an expression vector of the present invention or a reagent of the present invention and a pharmaceutically-acceptable carrier.
Yet another embodiment of the present invention is the use of an expression vector of the present invention or a reagent of the present invention for modulating the activity of a Serine/threonine kinase in a disease, preferably cancer, diabetes, a neurological disorder, a cardiovascular disorder, a musculo-skeletal disorder, a inflammatory disorder, a genitourological disorder or a respiratory disorder (e.g., asthma and COPD).
The invention thus provides a human serine/threonine kinase that can be used to identify test compounds that may act, for example, as activators or inhibitors at the enzyme's active site. Human serine/threonine kinase and fragments thereof also are useful in raising specific antibodies that can block the enzyme and effectively reduce its activity.
Polypeptides
Human serine/threonine kinase polypeptides according to the invention comprise at least 6, 10, 15, 20, 25, 50, 75, 100, 125, 150, 175, 200, 225, 250, 275, 300, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, or 1732 contiguous amino acids selected from the amino acid sequence shown in SEQ ID NO: 2 or a biologically active variant thereof, as defined below. A serine/threonine kinase polypeptide of the invention therefore can be a portion of a serine/threonine kinase protein, a full-length serine/threonine kinase protein, or a fusion protein comprising all or a portion of a serine/threonine kinase protein.
Biologically Active Variants
Human serine/threonine kinase polypeptide variants which are biologically active, e.g., retain enzymatic activity also are human serine/threonine kinase polypeptides. Preferably, naturally or non-naturally occurring human serine/threonine kinase polypeptide variants have amino acid sequences which are at least about 89, 90, 96, 97, 98, or 99% identical to the amino acid sequence shown in SEQ ID NO: 2 or a fragment thereof. Percent identity between a putative human serine/threonine kinase polypeptide variant and an amino acid sequence of SEQ ID NO: 2 is determined by conventional methods. See, for example, Altschul et al., Bull. Math. Bio. 48:603 (1986), and Henikoff & Henikoff, Proc. Natl. Acad Sci. USA 89:10915 (1992). Briefly, two amino acid sequences are aligned to optimize the alignment scores using a gap opening penalty of 10, a gap extension penalty of 1, and the “BLOSUM62” scoring matrix of Henikoff & Henikoff, 1992.
Those skilled in the art appreciate that there are many established algorithms available to align two amino acid sequences. The “FASTA” similarity search algorithm of Pearson & Lipman is a suitable protein alignment method for examining the level of identity shared by an amino acid sequence disclosed herein and the amino acid sequence of a putative variant. The FASTA algorithm is described by Pearson & Lipman, Proc. Nat'l Acad Sci. USA 85:2444(1988), and by Pearson, Meth. Enzymol. 183:63 (1990). Briefly, FASTA first characterizes sequence similarity by identifying regions shared by the query sequence (e.g., SEQ ID NO: 2) and a test sequence that have either the highest density of identities (if the ktup variable is 1) or pairs of identities (if ktup=2), without considering conservative amino acid substitutions, insertions, or deletions. The ten regions with the highest density of identities are then rescored by comparing the similarity of all paired amino acids using an amino acid substitution matrix, and the ends of the regions are “trimmed” to include only those residues that contribute to the highest score. If there are several regions with scores greater than the “cutoff” value (calculated by a predetermined formula based upon the length of the sequence the ktup value), then the trimmed initial regions are examined to determine whether the regions can be joined to form an approximate alignment with gaps. Finally, the highest scoring regions of the two amino acid sequences are aligned using a modification of the Needleman-Wunsch-Sellers algorithm (Needleman & Wunsch, J. Mol. Biol. 48:444 (1970); Sellers, SIAM J. Appl. Math. 26:787 (1974)), which allows for amino acid insertions and deletions. Preferred parameters for FASTA analysis are: ktup=1, gap opening penalty=10, gap extension penalty=1, and substitution matrix=BLOSUM62. These parameters can be introduced into a FASTA program by modifying the scoring matrix file (“SMATRIX”), as explained in Appendix 2 of Pearson, Meth. Enzymol. 183:63 (1990).
FASTA can also be used to determine the sequence identity of nucleic acid molecules using a ratio as disclosed above. For nucleotide sequence comparisons, the ktup value can range between one to six, preferably from three to six, most preferably three, with other parameters set as default.
Variations in percent identity can be due, for example, to amino acid substitutions, insertions, or deletions. Amino acid substitutions are defined as one for one amino acid replacements. They are conservative in nature when the substituted amino acid has similar structural and/or chemical properties. Examples of conservative replacements are substitution of a leucine with an isoleucine or valine, an aspartate with a glutamate, or a threonine with a serine.
Amino acid insertions or deletions are changes to or within an amino acid sequence. They typically fall in the range of about 1 to 5 amino acids. Guidance in determining which amino acid residues can be substituted, inserted, or deleted without abolishing biological or immunological activity of a human serine/threonine kinase polypeptide can be found using computer programs well known in the art, such as DNASTAR software.
The invention additionally, encompasses serine/threonine kinase polypeptides that are differentially modified during or after translation, e.g., by glycosylation, acetylation, phosphorylation, amidation, derivatization by known protecting/blocking groups, proteolytic cleavage, linkage to an antibody molecule or other cellular ligand, etc. Any of numerous chemical modifications can be carried out by known techniques including, but not limited, to specific chemical cleavage by cyanogen bromide, trypsin, chymotrypsin, papain, V8 protease, NaBH4, acetylation, formylation, oxidation, reduction, metabolic synthesis in the presence of tunicamycin, etc.
Additional post-translational modifications encompassed by the invention include, for example, e.g., N-linked or O-linked carbohydrate chains, processing of N-terminal or C-terminal ends), attachment of chemical moieties to the amino acid backbone, chemical modifications of N-linked or O-linked carbohydrate chains, and addition or deletion of an N-terminal methionine residue as a result of prokaryotic host cell expression. The serine/threonine kinase polypeptides may also be modified with a detectable label, such as an enzymatic, fluorescent, isotopic or affinity label to allow for detection and isolation of the protein.
The invention also provides chemically modified derivatives of serine/threonine kinase polypeptides that may provide additional advantages such as increased solubility, stability and circulating time of the polypeptide, or decreased immunogenicity (see U.S. Pat. No. 4,179,337). The chemical moieties for derivitization can be selected from water soluble polymers such as polyethylene glycol ethylene glycol/propylene glycol copolymers, carboxymethylcellulose, dextran, polyvinyl alcohol, and the like. The polypeptides can be modified at random or predetermined positions within the molecule and can include one, two, three, or more attached chemical moieties.
Whether an amino acid change or a polypeptide modification results in a biologically active serine/threonine kinase polypeptide can readily be determined by assaying for enzymatic activity, as described for example, in Trost et al., J. Biol. Chem. 275, 7373–77, 2000; Hayashi et al., Biochem. Biophys. Res. Commun. 264, 449–56, 1999; Masure et al., Eur. J. Biochem. 265, 353–60, 1999; and Mukhopadhyay et al., J. Bacteriol. 181, 6615–22, 1999.
Fusion Proteins
Fusion proteins are useful for generating antibodies against serine/threonine kinase polypeptide amino acid sequences and for use in various assay systems. For example, fusion proteins can be used to identify proteins that interact with portions of a human serine/threonine kinase polypeptide. Protein affinity chromatography or library-based assays for protein-protein interactions, such as the yeast two-hybrid or phage display systems, can be used for this purpose. Such methods are well known in the art and also can be used as drug screens.
A human serine/threonine kinase polypeptide fusion protein comprises two polypeptide segments fused together by means of a peptide bond. The first polypeptide segment comprises at least 6, 10, 15, 20, 25, 50, 75, 100, 125, 150, 175, 200, 225, 250, 275, 300, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, or 1732 contiguous amino acids of SEQ ID NO: 2 or of a biologically active variant, such as those described above. The first polypeptide segment also can comprise full-length serine/threonine kinase protein.
The second polypeptide segment can be a full-length protein or a protein fragment. Proteins commonly used in fusion protein construction include β-galactosidase, β-glucuronidase, green fluorescent protein (GFP), autofluorescent proteins, including blue fluorescent protein (BFP), glutathione-S-transferase (GST), luciferase, horseradish peroxidase (HRP), and chloramphenicol acetyltransferase (CAT).
Additionally, epitope tags are used in fusion protein constructions, including histidine (His) tags, FLAG tags, influenza hemagglutinin (HA) tags, Myc tags, VSV-G tags, and thioredoxin (Trx) tags. Other fusion constructions can include maltose binding protein (MBP), S-tag, Lex a DNA binding domain (DBD) fusions, GAL4 DNA binding domain fusions, and herpes simplex virus (HSV) BP16 protein fusions. A fusion protein also can be engineered to contain a cleavage site located between the serine/threonine kinase polypeptide-encoding sequence and the heterologous protein sequence, so that the serine/threonine kinase polypeptide can be cleaved and purified away from the heterologous moiety.
A fusion protein can be synthesized chemically, as is known in the art. Preferably, a fusion protein is produced by covalently linking two polypeptide segments or by standard procedures in the art of molecular biology. Recombinant DNA methods can be used to prepare fusion proteins, for example, by making a DNA construct which comprises coding sequences selected from SEQ ID NO: 1 in proper reading frame with nucleotides encoding the second polypeptide segment and expressing the DNA construct in a host cell, as is known in the art. Many kits for constructing fusion proteins are available from companies such as Promega Corporation (Madison, Wis.), Stratagene (La Jolla, Calif.), CLONTECH (Mountain View, Calif.), Santa Cruz Biotechnology (Santa Cruz, Calif.), MBL International Corporation (MIC; Watertown, Mass.), and Quantum Biotechnologies (Montreal, Canada; 1-888-DNA-KITS).
Identification of Species Homologs
Species homologs of human serine/threonine kinase polypeptide can be obtained using serine/threonine kinase polypeptide polynucleotides (described below) to make suitable probes or primers for screening cDNA expression libraries from other species, such as mice, monkeys, or yeast, identifying cDNAs which encode homologs of serine/threonine kinase polypeptide, and expressing the cDNAs as is known in the art.
Polynucleotides
A human serine/threonine kinase polynucleotide can be single- or double-stranded and comprises a coding sequence or the complement of a coding sequence for a serine/threonine kinase polypeptide. A coding sequence for human serine/threonine kinase is shown in SEQ ID NO: 1.
Degenerate nucleotide sequences encoding human serine/threonine kinase polypeptides, as well as homologous nucleotide sequences which are at least about 50, 55, 60, 65, 70, preferably about 75, 90, 96, 98, or 99% identical to the nucleotide sequence shown in SEQ ID NO: 1 or its complement also are serine/threonine kinase polynucleotides. Percent sequence identity between the sequences of two polynucleotides is determined using computer programs such as ALIGN which employ the FASTA algorithm, using an affine gap search with a gap open penalty of −12 and a gap extension penalty of −2. Complementary DNA (cDNA) molecules, species homologs, and variants of serine/threonine kinase polynucleotides that encode biologically active serine/threonine kinase polypeptides also are serine/threonine kinase polynucleotides. Polynucleotide fragments comprising at least 8, 9, 10, 11, 12, 15, 20, or 25 contiguous nucleotides of SEQ ID NO: 1 or its complement also are serine/threonine kinase polynucleotides. These fragments can be used, for example, as hybridization probes or as antisense oligonucleotides.
Identification of Polynucleotide Variants and Homologs
Variants and homologs of the serine/threonine kinase polynucleotides described above also are serine/threonine kinase polynucleotides. Typically, homologous serine/threonine kinase polynucleotide sequences can be identified by hybridization of candidate polynucleotides to known serine/threonine kinase polynucleotides under stringent conditions, as is known in the art. For example, using the following wash conditions—2×SSC (0.3 M NaCl, 0.03 M sodium citrate, pH 7.0), 0.1% SDS, room temperature twice, 30 minutes each; then 2×SSC, 0.1% SDS, 50° C. once, 30 minutes; then 2×SSC, room temperature twice, 10 minutes each—homologous sequences can be identified which contain at most about 25–30% basepair mismatches. More preferably, homologous nucleic acid strands contain 15–25% basepair mismatches, even more preferably 5–15% basepair mismatches.
Species homologs of the serine/threonine kinase polynucleotides disclosed herein also can be identified by making suitable probes or primers and screening cDNA expression libraries from other species, such as mice, monkeys, or yeast. Human variants of serine/threonine kinase polynucleotides can be identified, for example, by screening human cDNA expression libraries. It is well known that the Tm of a double-stranded DNA decreases by 1–1.5° C. with every 1% decrease in homology (Bonner et al., J. Mol. Biol. 81, 123 (1973). Variants of human serine/threonine kinase polynucleotides or serine/threonine kinase polynucleotides of other species can therefore be identified by hybridizing a putative homologous serine/threonine kinase polynucleotide with a polynucleotide having a nucleotide sequence of SEQ ID NO: 1 or the complement thereof to form a test hybrid. The melting temperature of the test hybrid is compared with the melting temperature of a hybrid comprising polynucleotides having perfectly complementary nucleotide sequences, and the number or percent of basepair mismatches within the test hybrid is calculated.
Nucleotide sequences which hybridize to serine/threonine kinase polynucleotides or their complements following stringent hybridization and/or wash conditions also are serine/threonine kinase polynucleotides. Stringent wash conditions are well known and understood in the art and are disclosed, for example, in Sambrook et al., MOLECULAR CLONING: A LABORATORY MANUAL, 2d ed., 1989, at pages 9.50–9.51.
Typically, for stringent hybridization conditions a combination of temperature and salt concentration should be chosen that is approximately 12–20° C. below the calculated Tm of the hybrid under study. The Tm of a hybrid between a serine/threonine kinase polynucleotide having a nucleotide sequence shown in SEQ ID NO: 1 or the complement thereof and a polynucleotide sequence which is at least about 50, preferably about 75, 90, 96, or 98% identical to one of those nucleotide sequences can be calculated, for example, using the equation of Bolton and McCarthy, Proc. Natl. Acad. Sci. U.S.A. 48, 1390 (1962):Tm=81.5° C.−16.6(log10[Na+])+0.41(% G+C)−0.63(% formamide)−600/l),                where l=the length of the hybrid in basepairs.        
Stringent wash conditions include, for example, 4×SSC at 65° C., or 50% formamide, 4×SSC at 42° C., or 0.5×SSC, 0.1% SDS at 65° C. Highly stringent wash conditions include, for example, 0.2×SSC at 65° C.
Preparation of Polynucleotides
A human serine/threonine kinase polynucleotide can be isolated free of other cellular components such as membrane components, proteins, and lipids. Polynucleotides can be made by a cell and isolated using standard nucleic acid purification techniques, or synthesized using an amplification technique, such as the polymerase chain reaction (PCR), or by using an automatic synthesizer. Methods for isolating polynucleotides are routine and are known in the art. Any such technique for obtaining a polynucleotide can be used to obtain isolated serine/threonine kinase polynucleotides. For example, restriction enzymes and probes can be used to isolate polynucleotide fragments, which comprise serine/threonine kinase nucleotide sequences. Isolated polynucleotides are in preparations that are free or at least 70, 80, or 90% free of other molecules.
Human serine/threonine kinase cDNA molecules can be made with standard molecular biology techniques, using serine/threonine kinase mRNA as a template. Human serine/threonine kinase cDNA molecules can thereafter be replicated using molecular biology techniques known in the art and disclosed in manuals such as Sambrook et al. (1989). An amplification technique, such as PCR, can be used to obtain additional copies of polynucleotides of the invention, using either human genomic DNA or cDNA as a template.
Alternatively, synthetic chemistry techniques can be used to synthesize serine/threonine kinase polynucleotides. The degeneracy of the genetic code allows alternate nucleotide sequences to be synthesized which will encode a human serine/threonine kinase polypeptide having, for example, an amino acid sequence shown in SEQ ID NO: 2 or a biologically active variant thereof.
Extending Polynucleotides
Various PCR-based methods can be used to extend the nucleic acid sequences disclosed herein to detect upstream sequences such as promoters and regulatory elements. For example, restriction-site PCR uses universal primers to retrieve unknown sequence adjacent to a known locus. Sarkar, PCR Methods Applic. 2, 318–322, 1993; Triglia et al., Nucleic Acids Res. 16, 8186, 1988; Lagerstrom et al., PCR Methods Applic. 1, 111–119, 1991; Parker et al., Nucleic Acids Res. 19, 3055–3060, 1991). Additionally, PCR, nested primers, and PROMOTERFINDER libraries (CLONTECH, Palo Alto, Calif.) can be used to walk genomic DNA (CLONTECH, Palo Alto, Calif.). See WO 01/98340
Obtaining Polynucleotides
Human serine/threonine kinase polypeptides can be obtained, for example, by purification from human cells, by expression of serine/threonine kinase polynucleotides, or by direct chemical synthesis.
Protein Purification
Human serine/threonine kinase polypeptides can be purified from any human cell which expresses the receptor, including host cells which have been transfected with serine/threonine kinase polynucleotides. A purified serine/threonine kinase polypeptide, is separated from other compounds that normally associate with the serine/threonine kinase polypeptide in the cell, such as certain proteins, carbohydrates, or lipids, using methods well-known in the art. Such methods include, but are not limited to, size exclusion chromatography, ammonium sulfate fractionation, ion exchange chromatography, affinity chromatography, and preparative gel electrophoresis.
A preparation of purified serine/threonine kinase polypeptides is at least 80% pure; preferably, the preparations are 90%, 95%, or 99% pure. Purity of the preparations can be assessed by any means known in the art, such as SDS-polyacrylamide gel electrophoresis.
Expression of Polynucleotides
To express a human serine/threonine kinase polynucleotide, the polynucleotide can be inserted into an expression vector which contains the necessary elements for the transcription and translation of the inserted coding sequence. Methods which are well known to those skilled in the art can be used to construct expression vectors containing sequences encoding serine/threonine kinase polypeptides and appropriate transcriptional and translational control elements. These methods include in vitro recombinant DNA techniques, synthetic techniques, and in vivo genetic recombination. Such techniques are described, for example, in Sambrook et al. (i989) and in Ausubel et al., CURRENT PROTOCOLS IN MOLECULAR BIOLOGY, John Wiley & Sons, New York, N.Y., 1989.
A variety of expression vector/host systems can be utilized to contain and express sequences encoding a human serine/threonine kinase polypeptide. These include, but are not limited to, microorganisms, such as bacteria transformed with recombinant bacteriophage, plasmid, or cosmid DNA expression vectors; yeast transformed with yeast expression vectors, insect cell systems infected with virus expression vectors (e.g., baculovirus), plant cell systems transformed with virus expression vectors (e.g., cauliflower mosaic virus, CaMV; tobacco mosaic virus, TMV) or with bacterial expression vectors (e.g., Ti or pBR322 plasmids), or animal cell systems. See WO 01/98340.
Host Cells
A host cell strain can be chosen for its ability to modulate the expression of the inserted sequences or to process the expressed serine/threonine kinase polypeptide in the desired fashion. Such modifications of the polypeptide include, but are not limited to, acetylation, carboxylation, glycosylation, phosphorylation, lipidation, and acylation. Post-translational processing which cleaves a “prepro” form of the polypeptide also can be used to facilitate correct insertion, folding and/or function. Different host cells that have specific cellular machinery and characteristic mechanisms for post-translational activities (e.g., CHO, HeLa, MDCK, HEK293, and WI38) are available from the American Type Culture Collection (ATCC; 10801 University Boulevard, Manassas, Va. 20110-2209) and can be chosen to ensure the correct modification and processing of the foreign protein. See WO 01/98340.
Alternatively, host cells which contain a human serine/threonine kinase polynucleotide and which express a human serine/threonine kinase polypeptide can be identified by a variety of procedures known to those of skill in the art. Examples include enzyme-linked immunosorbent assay (ELISA), radioimmunoassay (RIA), and fluorescence activated cell sorting (FACS). Hampton et al., SEROLOGICAL METHODS: A LABORATORY MANUAL, APS Press, St. Paul, Minn., 1990) and Maddox et al., J. Exp. Med 158, 1211–1216, 1983). See WO 01/98340.
A wide variety of labels and conjugation techniques are known by those skilled in the art and can be used in various nucleic acid and amino acid assays. Means for producing labeled hybridization or PCR probes for detecting sequences related to polynucleotides encoding serine/threonine kinase polypeptides include oligolabeling, nick translation, end-labeling, or PCR amplification using a labeled nucleotide. Alternatively, sequences encoding a human serine/threonine kinase polypeptide can be cloned into a vector for the production of an mRNA probe. Such vectors are known in the art, are commercially available, and can be used to synthesize RNA probes in vitro by addition of labeled nucleotides and an appropriate RNA polymerase such as T7, T3, or SP6. These procedures can be conducted using a variety of commercially available kits (Amersham Pharmacia Biotech, Promega, and US Biochemical). Suitable reporter molecules or labels which can be used for ease of detection include radionuclides, enzymes, and fluorescent, chemiluminescent, or chromogenic agents, as well as substrates, cofactors, inhibitors, magnetic particles, and the like.
Expression and Purification of Polypeptides
Host cells transformed with nucleotide sequences encoding a human serine/threonine kinase polypeptide can be cultured under conditions suitable for the expression and recovery of the protein from cell culture. The polypeptide produced by a transformed cell can be secreted or contained intracellularly depending on the sequence and/or the vector used. As will be understood by those of skill in the art, expression vectors containing polynucleotides which encode serine/threonine kinase polypeptides can be designed to contain signal sequences which direct secretion of soluble serine/threonine kinase polypeptides through a prokaryotic or eukaryotic cell membrane or which direct the membrane insertion of membrane-bound serine/threonine kinase polypeptide. See WO 01/98340.
Chemical Synthesis
Sequences encoding a human serine/threonine kinase polypeptide can be synthesized, in whole or in part, using chemical methods well known in the art (see Caruthers et al., Nucl. Acids Res. Symp. Ser. 215–223, 1980; Horn et al. Nucl. Acids Res. Symp. Ser. 225–232, 1980). Alternatively, a human serine/threonine kinase polypeptide itself can be produced using chemical methods to synthesize its amino acid sequence, such as by direct peptide synthesis using solid-phase techniques (Merrifield, J. Am. Chem. Soc. 85, 2149–2154, 1963; Roberge et al., Science 269, 202–204, 1995). Protein synthesis can be performed using manual techniques or by automation. Automated synthesis can be achieved, for example, using Applied Biosystems 431A Peptide Synthesizer (Perkin Elmer). Optionally, fragments of serine/threonine kinase polypeptides can be separately synthesized and combined using chemical methods to produce a full-length molecule. See WO 01/98340.
As will be understood by those of skill in the art, it may be advantageous to produce serine/threonine kinase polypeptide-encoding nucleotide sequences possessing non-naturally occurring codons. For example, codons preferred by a particular prokaryotic or eukaryotic host can be selected to increase the rate of protein expression or to produce an RNA transcript having desirable properties, such as a half-life which is longer than that of a transcript generated from the naturally occurring sequence.
The nucleotide sequences disclosed herein can be engineered using methods generally known in the art to alter serine/threonine kinase polypeptide-encoding sequences for a variety of reasons, including but not limited to, alterations which modify the cloning, processing, and/or expression of the polypeptide or mRNA product. DNA shuffling by random fragmentation and PCR reassembly of gene fragments and synthetic oligonucleotides can be used to engineer the nucleotide sequences. For example, site-directed mutagenesis can be used to insert new restriction sites, alter glycosylation patterns, change codon preference, produce splice variants, introduce mutations, and so forth.
Antibodies
Any type of antibody known in the art can be generated to bind specifically to an epitope of a human serine/threonine kinase polypeptide. “Antibody” as used herein includes intact immunoglobulin molecules, as well as fragments thereof, such as Fab, F(ab′)2, and Fv, which are capable of binding an epitope of a human serine/threonine kinase polypeptide. Typically, at least 6, 8, 10, or 12 contiguous amino acids are required to form an epitope. However, epitopes which involve non-contiguous amino acids may require more, e.g., at least 15, 25, or 50 amino acids.
An antibody which specifically binds to an epitope of a human serine/threonine kinase polypeptide can be used therapeutically, as well as in immunochemical assays, such as Western blots, ELISAs, radioimmunoassays, immunohistochemical assays, immunoprecipitations, or other immunochemical assays known in the art. Various immunoassays can be used to identify antibodies having the desired specificity. Numerous protocols for competitive binding or immunoradiometric assays are well known in the art. Such immunoassays typically involve the measurement of complex formation between an immunogen and an antibody that specifically binds to the immunogen.
Typically, an antibody that specifically binds to a human serine/threonine kinase polypeptide provides a detection signal at least 5-, 10-, or 20-fold higher than a detection signal provided with other proteins when used in an immunochemical assay. Preferably, antibodies that specifically bind to serine/threonine kinase polypeptides do not detect other proteins in immunochemical assays and can immunoprecipitate a human serine/threonine kinase polypeptide from solution. See WO 01/98340.
Antisense Oligonucleotides
Antisense oligonucleotides are nucleotide sequences that are complementary to a specific DNA or RNA sequence. Once introduced into a cell, the complementary nucleotides combine with natural sequences produced by the cell to form complexes and block either transcription or translation. Preferably, an antisense oligonucleotide is at least 11 nucleotides in length, but can be at least 12, 15, 20, 25, 30, 35, 40, 45, or 50 or more nucleotides long. Longer sequences also can be used. Antisense oligonucleotide molecules can be provided in a DNA construct and introduced into a cell as described above to decrease the level of serine/threonine kinase gene products in the cell.
Antisense oligonucleotides can be deoxyribonucleotides, ribonucleotides, or a combination of both. Oligonucleotides can be synthesized manually or by an automated synthesizer, by covalently linking the 5′ end of one nucleotide with the 3′ end of another nucleotide with non-phosphodiester internucleotide linkages such alkylphosphonates, phosphorothioates, phosphorodithioates, alkylphosphonothioates, alkylphosphonates, phosphoramidates, phosphate esters, carbamates, acetamidate, carboxymethyl esters, carbonates, and phosphate triesters. See Brown, Meth. Mol. Biol. 20, 1–8, 1994; Sonveaux, Meth. Mol. Biol. 26, 1–72, 1994; Uhlmann et al., Chem. Rev. 90, 543–583, 1990.
Modifications of serine/threonine kinase gene expression can be obtained by designing antisense oligonucleotides that will form duplexes to the control, 5′, or regulatory regions of the serine/threonine kinase gene. Oligonucleotides derived from the transcription initiation site, e.g., between positions −10 and +10 from the start site, are preferred. Similarly, inhibition can be achieved using “triple helix” base-pairing methodology. Triple helix pairing is useful because it causes inhibition of the ability of the double helix to open sufficiently for the binding of polymerases, transcription factors, or chaperons. Therapeutic advances using triplex DNA have been described in the literature (e.g., Gee et al., in Huber & Carr, MOLECULAR AND IMMUNOLOGIC APPROACHES, Futura Publishing Co., Mt. Kisco, N.Y., 1994). An antisense oligonucleotide also can be designed to block translation of mRNA by preventing the transcript from binding to ribosomes. See WO 01/98340.
Ribozymes
Ribozymes are RNA molecules with catalytic activity. See, e.g., Cech, Science 236, 1532–1539; 1987; Cech, Ann. Rev. Biochem. 59, 543–568; 1990, Cech, Curr. Opin. Struct. Biol. 2, 605–609; 1992, Couture & Stinchcomb, Trends Genet. 12, 510–515, 1996. Ribozymes can be used to inhibit gene function by cleaving an RNA sequence, as is known in the art (e.g., Haseloff et al., U.S. Pat. No. 5,641,673). The mechanism of ribozyme action involves sequence-specific hybridization of the ribozyme molecule to complementary target RNA, followed by endonucleolytic cleavage. Examples include engineered hammerhead motif ribozyme molecules that can specifically and efficiently catalyze endonucleolytic cleavage of specific nucleotide sequences.
The coding sequence of a human serine/threonine kinase polynucleotide can be used to generate ribozymes that will specifically bind to mRNA transcribed from the serine/threonine kinase polynucleotide. Methods of designing and constructing ribozymes which can cleave other RNA molecules in trans in a highly sequence specific manner have been developed and described in the art (see Haseloff et al. Nature 334, 585–591, 1988). For example, the cleavage activity of ribozymes can be targeted to specific RNAs by engineering a discrete “hybridization” region into the ribozyme. The hybridization region contains a sequence complementary to the target RNA and thus specifically hybridizes with the target (see, for example, Gerlach et al., EP 321,201). See WO 01/98340.
Differentially Expressed Genes
Described herein are methods for the identification of genes whose products interact with human serine/threonine kinase. Such genes may represent genes that are differentially expressed in disorders including, but not limited to, cancer, diabetes, neurological disorders, cardiovascular disorders, musculo-skeletal disorders, inflammatory disorders, genitourological disorders, and respiratory disorders (e.g., asthma and COPD). Further, such genes may represent genes that are differentially regulated in response to manipulations relevant to the progression or treatment of such diseases. Additionally, such genes may have a temporally modulated expression, increased or decreased at different stages of tissue or organism development. A differentially expressed gene may also have its expression modulated under control versus experimental conditions. In addition, the human serine/threonine kinase gene or gene product may itself be tested for differential expression.
The degree to which expression differs in a normal versus a diseased state need only be large enough to be visualized via standard characterization techniques such as differential display techniques. Other such standard characterization techniques by which expression differences may be visualized include but are not limited to, quantitative RT (reverse transcriptase), PCR, and Northern analysis.
To identify differentially expressed genes total RNA or, preferably, mRNA is isolated from tissues of interest. For example, RNA samples are obtained from tissues of experimental subjects and from corresponding tissues of control subjects. Any RNA isolation technique that does not select against the isolation of mRNA may be utilized for the purification of such RNA samples. See, for example, Ausubel et al., ed., CURRENT PROTOCOLS IN MOLECULAR BIOLOGY, John Wiley & Sons, Inc. New York, 1987–1993. Large numbers of tissue samples may readily be processed using techniques well known to those of skill in the art, such as, for example, the single-step RNA isolation process of Chomczynski, U.S. Pat. No. 4,843,155.
Transcripts within the collected RNA samples that represent RNA produced by differentially expressed genes are identified by methods well known to those of skill in the art. They include, for example, differential screening (Tedder et al., Proc. Natl. Acad Sci. U.S.A. 85, 208–12, 1988), subtractive hybridization (Hedrick et al., Nature 308, 149–53; Lee et al., Proc. Natl. Acad Sci. U.S.A. 88, 2825, 1984), and, preferably, differential display (Liang & Pardee, Science 257, 967–71, 1992; U.S. Pat. No. 5,262,311).
The differential expression information may itself suggest relevant methods for the treatment of disorders involving the human serine/threonine kinase. For example, treatment may include a modulation of expression of the differentially expressed genes and/or the gene encoding the human serine/threonine kinase. The differential expression information may indicate whether the expression or activity of the differentially expressed gene or gene product or the human serine/threonine kinase gene or gene product are up-regulated or down-regulated.
Screening Methods
The invention provides assays for screening test compounds that bind to or modulate the activity of a human serine/threonine kinase polypeptide or a human serine/threonine kinase polynucleotide. A test compound preferably binds to a human serine/threonine kinase polypeptide or polynucleotide. More preferably, a test compound decreases or increases enzymatic activity by at least about 10, preferably about 50, more preferably about 75, 90, or 100% relative to the absence of the test compound.
Test Compounds
Test compounds can be pharmacologic agents already known in the art or can be compounds previously unknown to have any pharmacological activity. The compounds can be naturally occurring or designed in the laboratory. They can be isolated from microorganisms, animals, or plants, and can be produced recombinantly, or synthesized by chemical methods known in the art. If desired, test compounds can be obtained using any of the numerous combinatorial library methods known in the art, including but not limited to, biological libraries, spatially addressable parallel solid phase or solution phase libraries, synthetic library methods requiring deconvolution, the “one-bead one-compound” library method, and synthetic library methods using affinity chromatography selection. The biological library approach is limited to polypeptide libraries, while the other four approaches are applicable to polypeptide, non-peptide oligomer, or small molecule libraries of compounds. See Lam, Anticancer Drug Des. 12, 145, 1997.
Methods for the synthesis of molecular libraries are well known in the art (see, for example, DeWitt et al., Proc. Natl. Acad. Sci. U.S.A. 90, 6909, 1993; Erb et al. Proc. Natl. Acad. Sci. U.S.A. 91, 11422, 1994; Zuckermann et al., J. Med. Chem. 37, 2678, 1994; Cho et al., Science 261, 1303, 1993; Carell et al., Angew. Chem. Int. Ed. Engl. 33, 2059, 1994; Carell et al., Angew. Chem. Int. Ed. Engl. 33, 2061; Gallop et al., J. Med. Chem. 37, 1233, 1994). Libraries of compounds can be presented in solution (see, e.g., Houghten, BioTechniques 13, 412–421, 1992), or on beads (Lam, Nature 354, 82–84, 1991), chips (Fodor, Nature 364, 555–556, 1993), bacteria or spores (Ladner, U.S. Pat. No. 5,223,409), plasmids (Cull et al., Proc. Natl. Acad. Sci. U.S.A. 89, 1865–1869, 1992), or phage (Scott & Smith, Science 249, 386–390, 1990; Devlin, Science 249, 404–406, 1990); Cwirla et al., Proc. Natl. Acad. Sci. 97, 6378–6382, 1990; Felici, J. Mol. Biol. 222, 301–310, 1991; and Ladner, U.S. Pat. No. 5,223,409).
High Throughput Screening
Test compounds can be screened for the ability to bind to serine/threonine kinase polypeptides or polynucleotides or to affect serine/threonine kinase activity or serine/threonine kinase gene expression using high throughput screening. Using high throughput screening, many discrete compounds can be tested in parallel so that large numbers of test compounds can be quickly screened. The most widely established techniques utilize 96-well microtiter plates. The wells of the microtiter plates typically require assay volumes that range from 50 to 500 μl. In addition to the plates, many instruments, materials, pipettors, robotics, plate washers, and plate readers are commercially available to fit the 96-well format,
Alternatively, “free format assays,” or assays that have no physical barrier between samples, can be used. For example, an assay using pigment cells (melanocytes) in a simple homogeneous assay for combinatorial peptide libraries is described by Jayawickreme et al., Proc. Natl. Acad. Sci. USA. 19, 1614–18 (1994). The cells are placed under agarose in petri dishes, then beads that carry combinatorial compounds are placed on the surface of the agarose. The combinatorial compounds are partially released the compounds from the beads. Active compounds can be visualized as dark pigment areas because, as the compounds diffuse locally into the gel matrix, the active compounds cause the cells to change colors.
Another example of a free format assay is described by Chelsky, “Strategies for Screening Combinatorial Libraries: Novel and Traditional Approaches,” reported at the First Annual Conference of The Society for Biomolecular Screening in Philadelphia, Pa. (Nov. 7–10, 1995). Chelsky placed a simple homogenous enzyme assay for carbonic anhydrase inside an agarose gel such that the enzyme in the gel would cause a color change throughout the gel. Thereafter, beads carrying combinatorial compounds via a photolinker were placed inside the gel and the compounds were partially released by UV-light. Compounds that inhibited the enzyme were observed as local zones of inhibition having less color change.
Yet another example is described by Salmon et al., Molecular Diversity 2, 57–63 (1996). In this example, combinatorial libraries were screened for compounds that had cytotoxic effects on cancer cells growing in agar.
Another high throughput screening method is described in Beutel et al., U.S. Pat. No. 5,976,813. In this method, test samples are placed in a porous matrix. One or more assay components are then placed within, on top of, or at the bottom of a matrix such as a gel, a plastic sheet, a filter, or other form of easily manipulated solid support. When samples are introduced to the porous matrix they diffuse sufficiently slowly, such that the assays can be performed without the test samples running together.
Binding Assays
For binding assays, the test compound is preferably a small molecule that binds to and occupies, for example, the active site of the serine/threonine kinase polypeptide, such that normal biological activity is prevented. Examples of such small molecules include, but are not limited to, small peptides or peptide-like molecules.
In binding assays, either the test compound or the serine/threonine kinase polypeptide can comprise a detectable label, such as a fluorescent, radioisotopic, chemiluminescent, or enzymatic label, such as horseradish peroxidase, alkaline phosphatase, or luciferase. Detection of a test compound that is bound to the serine/threonine kinase polypeptide can then be accomplished, for example, by direct counting of radioemmission, by scintillation counting, or by determining conversion of an appropriate substrate to a detectable product.
Alternatively, binding of a test compound to a human serine/threonine kinase polypeptide can be determined without labeling either of the interactants. For example, a microphysiometer can be used to detect binding of a test compound with a human serine/threonine kinase polypeptide. A microphysiometer (e.g., Cytosensor™) is an analytical instrument that measures the rate at which a cell acidifies its environment using a light-addressable potentiometric sensor (LAPS). Changes in this acidification rate can be used as an indicator of the interaction between a test compound and a human serine/threonine kinase polypeptide (McConnell et al., Science 257, 1906–1912, 1992).
Determining the ability of a test compound to bind to a human serine/threonine kinase polypeptide also can be accomplished using a technology such as real-time Bimolecular Interaction Analysis (BIA) (Sjolander & Urbaniczky, Anal. Chem. 63, 2338–2345, 1991, and Szabo et al., Curr. Opin. Struct. Biol. 5, 699–705, 1995). BIA is a technology for studying biospecific interactions in real time, without labeling any of the interactants (e.g., BIAcore™). Changes in the optical phenomenon surface plasmon resonance (SPR) can be used as an indication of real-time reactions between biological molecules.
In yet another aspect of the invention, a human serine/threonine kinase polypeptide can be used as a “bait protein” in a two-hybrid assay or three-hybrid assay (see, e.g., U.S. Pat. No. 5,283,317; Zervos et al., Cell 72, 223–232, 1993; Madura et al., J. Biol. Chem. 268, 12046–12054, 1993; Bartel et al., BioTechniques 14, 920–924, 1993; Iwabuchi et al., Oncogene 8, 1693–1696, 1993; and Brent WO94/10300), to identify other proteins which bind to or interact with -the serine/threonine kinase polypeptide and modulate its activity.
The two-hybrid system is based on the modular nature of most transcription factors, which consist of separable DNA-binding and activation domains. Briefly, the assay utilizes two different DNA constructs. For example, in one construct, polynucleotide encoding a human serine/threonine kinase polypeptide can be fused to a polynucleotide encoding the DNA binding domain of a known transcription factor (e.g., GAL-4). In the other construct a DNA sequence that encodes an unidentified protein (“prey” or “sample”) can be fused to a polynucleotide that codes for the activation domain of the known transcription factor. If the “bait” and the “prey” proteins are able to interact in vivo to form an protein-dependent complex, the DNA-binding and activation domains of the transcription factor are brought into close proximity. This proximity allows transcription of a reporter gene (e.g., LacZ), which is operably linked to a transcriptional regulatory site responsive to the transcription factor. Expression of the reporter gene can be detected, and cell colonies containing the functional transcription factor can be isolated and used to obtain the DNA sequence encoding the protein that interacts with the serine/threonine kinase polypeptide.
It may be desirable to immobilize either the serine/threonine kinase polypeptide (or polynucleotide) or the test compound to facilitate separation of bound from unbound forms of one or both of the interactants, as well as to accommodate automation of the assay. Thus, either the serine/threonine kinase polypeptide (or polynucleotide) or the test compound can be bound to a solid support. Suitable solid supports include, but are not limited to, glass or plastic slides, tissue culture plates, microtiter wells, tubes, silicon chips, or particles such as beads (including, but not limited to, latex, polystyrene, or glass beads). Any method known in the art can be used to attach the polypeptide (or polynucleotide) or test compound to a solid support, including use of covalent and non-covalent linkages, passive absorption, or pairs of binding moieties attached respectively to the polypeptide (or polynucleotide) or test compound and the solid support. Test compounds are preferably bound to the solid support in an array, so that the location of individual test compounds can be tracked. Binding of a test compound to a human serine/threonine kinase polypeptide (or polynucleotide) can be accomplished in any vessel suitable for containing the reactants. Examples of such vessels include microtiter plates, test tubes, and microcentrifuge tubes.
In one embodiment, the serine/threonine kinase polypeptide is a fusion protein comprising a domain that allows the serine/threonine kinase polypeptide to be bound to a solid support. For example, glutathione-S-transferase fusion proteins can be adsorbed onto glutathione sepharose beads (Sigma Chemical, St. Louis, Mo.) or glutathione derivatized microtiter plates, which are then combined with the test compound or the test compound and the non-adsorbed serine/threonine kinase polypeptide; the mixture is then incubated under conditions conducive to complex formation (e.g., at physiological conditions for salt and pH). Following incubation, the beads or microtiter plate wells are washed to remove any unbound components. Binding of the interactants can be determined either directly or indirectly, as described above. Alternatively, the complexes can be dissociated from the solid support before binding is determined.
Other techniques for immobilizing proteins or polynucleotides on a solid support also can be used in the screening assays of the invention. For example, either a human serine/threonine kinase polypeptide (or polynucleotide) or a test compound can be immobilized utilizing conjugation of biotin and streptavidin. Biotinylated serine/threonine kinase polypeptides (or polynucleotides) or test compounds can be prepared from biotin-NHS(N-hydroxysuccinimide) using techniques well known in the art (e.g., biotinylation kit, Pierce Chemicals, Rockford, Ill.) and immobilized in the wells of streptavidin-coated 96 well plates (Pierce Chemical). Alternatively, antibodies which specifically bind to a serine/threonine kinase polypeptide, polynucleotide, or a test compound, but which do not interfere with a desired binding site, such as the active site of the serine/threonine kinase polypeptide, can be derivatized to the wells of the plate. Unbound target or protein can be trapped in the wells by antibody conjugation.
Methods for detecting such complexes, in addition to those described above for the GST-immobilized complexes, include immunodetection of complexes using antibodies which specifically bind to the serine/threonine kinase polypeptide or test compound, enzyme-linked assays which rely on detecting an activity of the serine/threonine kinase polypeptide, and SDS gel electrophoresis under non-reducing conditions.
Screening for test compounds which bind to a human serine/threonine kinase polypeptide or polynucleotide also can be carried out in an intact cell. Any cell which comprises a serine/threonine kinase polypeptide or polynucleotide can be used in a cell-based assay system. A serine/threonine kinase polynucleotide can be naturally occurring in the cell or can be introduced using techniques such as those described above. Binding of the test compound to a serine/threonine kinase polypeptide or polynucleotide is determined as described above.
Enzymatic Activity
Test compounds can be tested for the ability to increase or decrease the enzymatic activity of a human serine/threonine kinase polypeptide. Enzymatic activity can be measured, for example, as described in Trost et al., J. Biol. Chem., 275, 7373–77, 2000; Hayashi et al., Biochem. Biophys. Res. Commun. 264, 449–56, 1999; Masure et al., Eur. J. Biochem. 265, 353–60, 1999; and Mukhopadhyay et al., J. Bacteriol. 181, 6615–22, 1999.
Enzyme assays can be carried out after contacting either a purified serine/threonine kinase polypeptide, a cell membrane preparation, or an intact cell with a test compound. A test compound that decreases enzymatic activity of a human serine/threonine kinase polypeptide by at least about 10, preferably about 50, more preferably about 75, 90, or 100% is identified as a potential therapeutic agent for decreasing serine/threonine kinase activity. A test compound which increases enzymatic activity of a human serine/threonine kinase polypeptide by at least about 10, preferably about 50, more preferably about 75, 90, or 100% is identified as a potential therapeutic agent for increasing human serine/threonine kinase activity.
Gene Expression
In another embodiment, test compounds that increase or decrease serine/threonine kinase gene expression are identified. A serine/threonine kinase polynucleotide is contacted with a test compound, and the expression of an RNA or polypeptide product of the serine/threonine kinase polynucleotide is determined. The level of expression of appropriate mRNA or polypeptide in the presence of the test compound is compared to the level of expression of mRNA or polypeptide in the absence of the test compound. The test compound can then be identified as a modulator of expression based on this comparison. For example, when expression of mRNA or polypeptide is greater in the presence of the test compound than in its absence, the test compound is identified as a stimulator or enhancer of the mRNA or polypeptide expression. Alternatively, when expression of the mRNA or polypeptide is less in the presence of the test compound than in its absence, the test compound is identified as an inhibitor of the mRNA or polypeptide expression.
The level of serine/threonine kinase mRNA or polypeptide expression in the cells can be determined by methods well known in the art for detecting mRNA or polypeptide. Either qualitative or quantitative methods can be used. The presence of polypeptide products of a human serine/threonine kinase polynucleotide can be determined, for example, using a variety of techniques known in the art, including immunochemical methods such as radioimmunoassay, Western blotting, and immunohistochemistry. Alternatively, polypeptide synthesis can be determined in vivo, in a cell culture, or in an in vitro translation system by detecting incorporation of labeled amino acids into a human serine/threonine kinase polypeptide.
Such screening can be carried out either in a cell-free assay system or in an intact cell. Any cell that expresses a human serine/threonine kinase polynucleotide can be used in a cell-based assay system. The serine/threonine kinase polynucleotide can be naturally occurring in the cell or can be introduced using techniques such as those described above. Either a primary culture or an established cell line, such as CHO or human embryonic kidney 293 cells, can be used.
Pharmaceutical Compositions
The invention also provides pharmaceutical compositions that can be administered to a patient to achieve a therapeutic effect. Pharmaceutical compositions of the invention can comprise, for example, a human serine/threonine kinase polypeptide, serine/threonine kinase polynucleotide, ribozymes or antisense oligonucleotides, antibodies which specifically bind to a serine/threonine kinase polypeptide, or mimetics, activators, or inhibitors of a human serine/threonine kinase polypeptide activity. The compositions can be administered alone or in combination with at least one other agent, such as stabilizing compound, which can be administered in any sterile, biocompatible pharmaceutical carrier, including, but not limited to, saline, buffered saline, dextrose, and water. The compositions can be administered to a patient alone, or in combination with other agents, drugs or hormones.
In addition to the active ingredients, these pharmaceutical compositions can contain suitable pharmaceutically-acceptable carriers comprising excipients and auxiliaries that facilitate processing of the active compounds into preparations which can be used pharmaceutically. Pharmaceutical compositions of the invention can be administered by any number of routes including, but not limited to, oral, intravenous, intramuscular, intra-arterial, intramedullary, intrathecal, intraventricular, transdermal, subcutaneous, intraperitoneal, intranasal, parenteral, topical, sublingual, or rectal means. Pharmaceutical compositions for oral administration can be formulated using pharmaceutically acceptable carriers well known in the art in dosages suitable for oral administration. Such carriers enable the pharmaceutical compositions to be formulated as tablets, pills, dragees, capsules, liquids, gels, syrups, slurries, suspensions, and the like, for ingestion by the patient.
Pharmaceutical preparations for oral use can be obtained through combination of active compounds with solid excipient, optionally grinding a resulting mixture, and processing the mixture of granules, after adding suitable auxiliaries, if desired, to obtain tablets or dragee cores. Suitable excipients are carbohydrate or protein fillers, such as sugars, including lactose, sucrose, mannitol, or sorbitol; starch from corn, wheat, rice, potato, or other plants; cellulose, such as methyl cellulose, hydroxypropylmethyl-cellulose, or sodium carboxymethylcellulose; gums including arabic and tragacanth; and proteins such as gelatin and collagen. If desired, disintegrating or solubilizing agents can be added, such as the cross-linked polyvinyl pyrrolidone, agar, alginic acid, or a salt thereof such as sodium alginate.
Dragee cores can be used in conjunction with suitable coatings, such as concentrated sugar solutions, which also can contain gum arabic, talc, polyvinylpyrrolidone, carbopol gel, polyethylene glycol, and/or titanium dioxide, lacquer solutions, and suitable organic solvents or solvent mixtures. Dyestuffs or pigments can be added to the tablets or dragee coatings for product identification or to characterize the quantity of active compound, i.e., dosage.
Pharmaceutical preparations that can be used orally include push-fit capsules made of gelatin, as well as soft, sealed capsules made of gelatin and a coating, such as glycerol or sorbitol. Push-fit capsules can contain active ingredients mixed with a filler or binders, such as lactose or starches, lubricants, such as talc or magnesium stearate, and, optionally, stabilizers. In soft capsules, the active compounds can be dissolved or suspended in suitable liquids, such as fatty oils, liquid, or liquid polyethylene glycol with or without stabilizers.
Pharmaceutical formulations suitable for parenteral administration can be formulated in aqueous solutions, preferably in physiologically compatible buffers such as Hanks' solution, Ringer's solution, or physiologically buffered saline. Aqueous injection suspensions can contain substances that increase the viscosity of the suspension, such as sodium carboxymethyl cellulose, sorbitol, or dextran. Additionally, suspensions of the active compounds can be prepared as appropriate oily injection suspensions. Suitable lipophilic solvents or vehicles include fatty oils such as sesame oil, or synthetic fatty acid esters, such as ethyl oleate or triglycerides, or liposomes. Non-lipid polycationic amino polymers also can be used for delivery. Optionally, the suspension also can contain suitable stabilizers or agents that increase the solubility of the compounds to allow for the preparation of highly concentrated solutions. For topical or nasal administration, penetrants appropriate to the particular barrier to be permeated are used in the formulation. Such penetrants are generally known in the art.
The pharmaceutical compositions of the present invention can be manufactured in a manner that is known in the art, e.g., by means of conventional mixing, dissolving, granulating, dragee-making, levigating, emulsifying, encapsulating, entrapping, or lyophilizing processes. The pharmaceutical composition can be provided as a salt and can be formed with many acids, including but not limited to, hydrochloric, sulfuric, acetic, lactic, tartaric, malic, succinic, etc. Salts tend to be more soluble in aqueous or other protonic solvents than are the corresponding free base forms. In other cases, the preferred preparation can be a lyophilized powder which can contain any or all of the following: 1–50 mM histidine, 0.1%–2% sucrose, and 2–7% mannitol, at a pH range of 4.5 to 5.5, that is combined with buffer prior to use.
Further details on techniques for formulation and administration can be found in the latest edition of REMINGTON's PHARMACEUTCAL SCIENCES (Maack Publishing Co., Easton, Pa.). After pharmaceutical compositions have been prepared, they can be placed in an appropriate container and labeled for treatment of an indicated condition. Such labeling would include amount, frequency, and method of administration.
Therapeutic Indications and Methods
Human serine/threonine kinase can be regulated to treat cancer, diabetes, neurological disorders, cardiovascular disorders, musculo-skeletal disorders, inflammatory disorders, genitourological disorders, and respiratory disorders (e.g., asthma and COPD).
Cancer
Human serine/threonine kinase is highly expressed in the following cancer tissues: kidney tumor. Expression in the above-mentioned tissues and in particular the differential expression between diseased tissue and healthy tissue demonstrates that human serine/threonine kinase protein or mRNA can be used to diagnose cancer. In addition, the activity of human serine/threonine kinase can be modulated to treat cancer.
Cancer is a disease fundamentally caused by oncogenic cellular transformation. There are several hallmarks of transformed cells that distinguish them from their normal counterparts and underlie the pathophysiology of cancer. These include uncontrolled cellular proliferation, unresponsiveness to normal death-inducing signals (immortalization), increased cellular motility and invasiveness, increased ability to recruit blood supply through induction of new blood vessel formation (angiogenesis), genetic instability, and dysregulated gene expression. Various combinations of these aberrant physiologies, along with the acquisition of drug-resistance frequently lead to an intractable disease state in which organ failure and patient death ultimately ensue.
Most standard canter therapies target cellular proliferation and rely on the differential proliferative capacities between transformed and normal cells for their efficacy. This approach is hindered by the facts that several important normal cell types are also highly proliferative and that cancer cells frequently become resistant to these agents. Thus, the therapeutic indices for traditional anti-cancer therapies rarely exceed 2.0.
The advent of genomics-driven molecular target identification has opened up the possibility of identifying new cancer-specific targets for therapeutic intervention that will provide safer, more effective treatments for cancer patients. Thus, newly discovered tumor-associated genes and their products can be tested for their role(s) in disease and used as tools to discover and develop innovative therapies. Genes playing important roles in any of the physiological processes outlined above can be characterized as cancer targets.
Genes or gene fragments identified through genomics can readily be expressed in one or more heterologous expression systems to produce functional recombinant proteins. These proteins are characterized in vitro for their biochemical properties and then used as tools in high-throughput molecular screening programs to identify chemical modulators of their biochemical activities. Agonists and/or antagonists of target protein activity can be identified in this manner and subsequently tested in cellular and in vivo disease models for anti-cancer activity. Optimization of lead compounds with iterative testing in biological models and detailed pharmacokinetic and toxicological analyses form the basis for drug development and subsequent testing in humans.
Cancer disorders within the scope of the invention comprise any disease of an organ or tissue in mammals characterized by poorly controlled or uncontrolled multiplication of normal or abnormal cells in that tissue and its effect on the body as a whole. Cancer diseases within the scope of the invention comprise benign neoplasms, dysplasias, hyperplasias as well as neoplasms showing metastatic growth or any other transformations, e.g., leukoplalias, which often precede a breakout of cancer. Cells and tissues are cancerous when they grow more rapidly than normal cells, displacing or spreading into the surrounding healthy tissue or any other tissues of the body described as metastatic growth, assume abnormal shapes and sizes, show changes in their nucleocytoplasmatic ratio, nuclear polychromasia, and finally may cease.
Cancerous cells and tissues may affect the body as a whole when causing paraneoplastic syndromes or if cancer occurs within a vital organ or tissue, normal function will be impaired or halted, with possible fatal results. The ultimate involvement of a vital organ by cancer, either primary or metastatic, may lead to the death of the mammal affected. Cancer tends to spread, and the extent of its spread is usually related to an individual's chances of surviving the disease. Cancers are generally said to be in one of three stages of growth: early, or localized, when a tumor is still confined to the tissue of origin, or primary site; direct extension, where cancer cells from the tumour have invaded adjacent tissue or have spread only to regional lymph nodes; or metastasis, in which cancer cells have migrated to distant parts of the body from the primary site, via the blood or lymph systems, and have established secondary sites of infection. Cancer is said to be malignant because of its tendency to cause death if not treated.
Benign tumors usually do not cause death, although they may if they interfere with a normal body function by virtue of their location, size, or paraneoplastic side effects. Hence, benign tumors fall under the definition of cancer within the scope of the invention as well. In general, cancer cells divide at a higher rate than do normal cells, but the distinction between the growth of cancerous and normal tissues is not so much the rapidity of cell division in the former as it is the partial or complete loss of growth restraint in cancer cells and their failure to differentiate into a useful, limited tissue of the type that characterizes the functional equilibrium of growth of normal tissue.
Cancer tissues may express certain molecular receptors and probably are influenced by the host's susceptibility and immunity and it is known that-certain cancers of the breast and prostate, for example, are considered dependent on specific hormones for their existence. The term “cancer” under the scope of the invention is not limited to simple benign neoplasia but includes any other benign and malign neoplasia, such as 1) carcinoma, 2) sarcoma, 3) carcinosarcoma, 4) cancers of the blood-forming tissues, 5) tumors of nerve tissues including the brain, and 6) cancer of skin cells.
Carcinoma occurs in epithelial tissues, which cover the outer body (the skin) and line mucous membranes and the inner cavitary structures of organs e.g. such as the breast, lung, the respiratory and gastrointestinal tracts, the endocrine glands, and the genitourinary system. Ductal or glandular elements may persist in epithelial tumors, as in adenocarcinomas, e.g., thyroid adenocarcinoma, gastric adenocarcinoma, uterine adenocarcinoma. Cancers of the pavement-cell epithelium of the skin and of certain mucous membranes, such as cancers of the tongue, lip, larynx, urinary bladder, uterine cervix, or penis, may be termed epidermoid or squamous-cell carcinomas of the respective tissues and are within the scope of the definition of cancer as well.
Sarcomas develop in connective tissues, including fibrous tissues, adipose (fat) tissues, muscle, blood vessels, bone, and cartilage such as osteogenic sarcoma, liposarcoma, fibrosarcoma, and synovial sarcoma.
Carcinosarcoma is cancer that develops in both epithelial and connective tissue. Cancer disease within the scope of this definition may be primary or secondary, whereby primary indicates that the cancer originated in the tissue where it is found rather than was established as a secondary site through metastasis from another lesion. Cancers and tumor diseases within the scope of this definition may be benign or malign and may affect all anatomical structures of the body of a mammal. By example, to they comprise cancers and tumor diseases of I) the bone marrow and bone marrow derived cells (leukemias), II) the endocrine and exocrine glands, such as the thyroid, parathyroid, pituitary, adrenal glands, salivary glands, and pancreas III) the breast, such as benign or malignant tumors in the mammary glands of either a male or a female, the mammary ducts, adenocarcinoma, medullary carcinoma, comedocarcinoma, Paget's disease of the nipple, inflammatory carcinoma of the young woman, IV) the lung, V) the stomach, VI) the liver and spleen, VII) the small intestine, VIII) the colon, IX) the bone and its supportive and connective tissues such as malignant or benign bone tumour, such as malignant osteogenic sarcoma, benign osteoma, cartilage tumors, malignant chondrosarcoma or benign chondroma, bone marrow tumors such as malignant myeloma or benign eosinophilic granuloma, as well as metastatic tumors from bone tissues at other locations of the body; X) the mouth, throat, larynx, and the esophagus, XI) the urinary bladder and the internal and external organs and structures of the urogenital system of male and female such as the ovaries, uterus, cervix of the uterus, testes, and prostate gland, XII) the prostate, XIII) the pancreas, such as ductal carcinoma of the pancreas; XIV) the lymphatic tissue such as lymphomas and other tumors of lymphoid origin, XV) the skin, XVI) cancers and tumor diseases of all anatomical structures belonging to the respiratory systems including thoracal muscles and linings, XVI) primary or secondary cancer of the lymph nodes, XVIII) the tongue and of the bony structures of the hard palate or sinuses, XVIV) the mouth, cheeks, neck and salivary glands, XX) the blood vessels including the heart and their linings, XXI) the smooth or skeletal muscles and their ligaments and linings, XXII) the peripheral, the autonomous, the central nervous system including the cerebellum, and XXIII) the adipose tissue.
Protein phosphorylation is an essential component in intracellular signaling, with diverse and crucial functions including mediation of cell proliferation, survival, apoptosis, differentiation, migration and attachment. It is regulated by the balance between the opposing activities of protein kinases and protein phosphatases. Protein phosphorylation is mainly mediated by two types of protein kinases—protein tyrosine kinases and protein serine/threorine kinases. A number of protein tyrosine kinases are encoded by proto-oncogenes or viral oncogenes, and are thus strongly implicated in cancer. Protein serine/threonine kinases are known to play a role in intracellular signal transduction mediated by growth factors, cytokines, etc. inducing either cell proliferation, apoptosis or differentiation. Inhibitors of protein kinases are expected to provide efficacious therapeutic agents for the treatment of cancer.
Diabetes
Diabetes mellitus is a common metabolic disorder characterized by an abnormal elevation in blood glucose, alterations in lipids and abnormalities (complications) in the cardiovascular system, eye, kidney and nervous system. Diabetes is divided into two separate diseases: type 1 diabetes (juvenile onset), which results from a loss of cells which make and secrete insulin, and type 2 diabetes (adult onset), which is caused by a defect in insulin secretion and a defect in insulin action.
Type I diabetes is initiated by an autoimmune reaction that attacks the insulin secreting cells (beta cells) in the pancreatic islets. Agents that prevent this reaction from occurring or that stop the reaction before destruction of the beta cells has been accomplished are potential therapies for this disease. Other agents that induce beta cell proliferation and regeneration also are potential therapies.
Type II diabetes is the most common of the two diabetic conditions (6% of the population). The defect in insulin secretion is an important cause of the diabetic condition and results from an inability of the beta cell to properly detect and respond to rises in blood glucose levels with insulin release. Therapies that increase the response by the beta cell to glucose would offer an important new treatment for this disease.
The defect in insulin action in Type II diabetic subjects is another target for therapeutic intervention. Agents that increase the activity of the insulin receptor in muscle, liver, and fat will cause a decrease in blood glucose and a normalization of plasma lipids. The receptor activity can be increased by agents that directly stimulate the receptor or that increase the intracellular signals from the receptor. Other therapies can directly activate the cellular end process, i.e. glucose transport or various enzyme systems, to generate an insulin-like effect and therefore a produce beneficial outcome. Because overweight subjects have a greater susceptibility to Type II diabetes, any agent that reduces body weight is a possible therapy.
Both Type I and Type diabetes can be treated with agents that mimic insulin action or that treat diabetic complications by reducing blood glucose levels. Likewise, agents that reduces new blood vessel growth can be used to treat the eye complications that develop in both diseases.
Neurological Disorders
Human serine/threonine kinase is highly expressed in the following brain tissues: fetal brain, brain, Alzheimer brain, cerebellum, cerebellum (right), cerebellum (left), cerebral cortex, Alzheimer cerebral cortex, frontal lobe, Alzheimer brain frontal lobe, occipital lobe, parietal lobe, temporal lobe, precentral gyrus, tonsilla cerebelli, vermis cerebelli, pons, cerebral peduncles, corpus callosum, hippocampus, thalamus, spinal cord The expression in brain tissues and in particular the differential expression between diseased tissue and healthy tissue demonstrates that human serine/threonine kinase protein or mRNA can be used to diagnose nervous system diseases. In addition, the activity of human serine/threonine kinase can be modulated to treat nervous system diseases.
Central and peripheral nervous system disorders can be treated, such as primary and secondary disorders after brain injury, disorders of mood, anxiety disorders, disorders of thought and volition, disorders of sleep and wakefulness, diseases of the motor unit, such as neurogenic and myopathic disorders, neurodegenerative disorders such as Alzheimer's and Parkinson's disease, and processes of peripheral and chronic pain.
Pain that is associated with peripheral or central nervous system disorders also can be treated by regulating the activity of human serine/threonine kinase. Pain which can be treated includes that associated with central nervous system disorders, such as multiple sclerosis, spinal cord injury, sciatica, failed back surgery syndrome, traumatic brain injury, epilepsy, Parkinson's disease, post-stroke, and vascular lesions in the brain and spinal cord (e.g., infarct, hemorrhage, vascular malformation). Non-central neuropathic pain includes that associated with post mastectomy pain, reflex sympathetic dystrophy (RSD), trigeminal neuralgiaradioculopathy, post-surgical pain, HIV/AIDS related pain, cancer pain, metabolic neuropathies (e.g., diabetic neuropathy, vasculitic neuropathy secondary to connective tissue disease), paraneoplastic polyneuropathy associated, for example, with carcinoma of lung, or leukemia, or lymphoma, or carcinoma of prostate, colon or stomach, trigeminal neuralgia, cranial neuralgias, and post-herpetic neuralgia Pain associated with cancer and cancer treatment also can be treated, as can headache pain (for example, migraine with aura, migraine without aura, and other migraine disorders), episodic and chronic tension-type headache, tension-type like headache, cluster headache, and chronic paroxysmal hemicrania.
Cardiovascular Disorders
Human serine/threonine kinase is highly expressed in the following cardiovascular related tissues: heart, pericardium, heart atrium (right), heart atrium (left), heart ventricle (left), interventricular septum. Expression in the above-mentioned tissues demonstrates that human serine/threonine kinase protein or mRNA can be used to diagnose cardiovascular diseases. In addition, the activity of human serine/threonine kinase can be modulated to treat cardiovascular diseases.
Heart failure is defined as a pathophysiological state in which an abnormality of cardiac function is responsible for the failure of the heart to pump blood at a rate commensurate with the requirement of the metabolizing tissue. It includes all forms of pumping failures such as high-output and low-output, acute and chronic, right-sided or left-sided, systolic or diastolic, independent of the underlying cause.
Myocardial infarction (MI) is generally caused by an abrupt decrease in coronary blood flow that follows a thrombotic occlusion of a coronary artery previously narrowed by arteriosclerosis. MI prophylaxis (primary and secondary prevention) is included as well as the acute treatment of MI and the prevention of complications.
Ischemic diseases are conditions in which the coronary flow is restricted resulting in a perfusion which is inadequate to meet the myocardial requirement for oxygen. This group of diseases includes stable angina, unstable angina and asymptomatic ischemia.
Arrhythmias include all forms of atrial and ventricular tachyarrhythmias, atrial tachycardia, atrial flutter, atrial fibrillation, atrio-ventricular reentrant tachycardia, preexitation syndrome, ventricular tachycardia, ventricular flutter, ventricular fibrillation, as well as bradycardic forms of arrhythmias.
Hypertensive vascular diseases include primary as well as all kinds of secondary arterial hypertension, renal, endocrine, neurogenic, others. The genes may be used as drug targets for the treatment of hypertension as well as for the prevention of all complications arising from cardiovascular diseases.
Peripheral vascular diseases are defined as vascular diseases in which arterial and/or venous flow is reduced resulting in an imbalance between blood supply and tissue oxygen demand. It includes chronic peripheral arterial occlusive disease (PAOD), acute arterial thrombosis and embolism, inflammatory vascular disorders, Raynaud's phenomenon and venous disorders.
Atherosclerosis is a cardiovascular disease in which the vessel wall is remodeled, compromising the lumen of the vessel. The atherosclerotic remodeling process involves accumulation of cells, both smooth muscle cells and monocyte/macrophage inflammatory cells, in the intima of the vessel wall. These cells take up lipid, likely from the circulation, to form a mature atherosclerotic lesion. Although the formation of these lesions is a chronic process, occurring over decades of an adult human life, the majority of the morbidity associated with atherosclerosis occurs when a lesion ruptures, releasing thrombogenic debris that rapidly occludes the artery. When such an acute event occurs in the coronary artery, myocardial infarction can ensue, and in the worst case, can result in death.
The formation of the atherosclerotic lesion can be considered to occur in five overlapping stages such as migration, lipid accumulation, recruitment of inflammatory cells, proliferation of vascular smooth muscle cells, and extracellular matrix deposition. Each of these processes can be shown to occur in man and in animal models of atherosclerosis, but the relative contribution of each to the pathology and clinical significance of the lesion is unclear.
Thus, a need exists for therapeutic methods and agents to treat cardiovascular pathologies, such as atherosclerosis and other conditions related to coronary artery disease.
Cardiovascular diseases include but are not limited to disorders of the heart and the vascular system, such as congestive heart failure, myocardial infarction, ischemic diseases of the heart, all kinds of atrial and ventricular arrhythmias, hypertensive vascular diseases, peripheral vascular diseases, and atherosclerosis.
Levels of fats in the bloodstream that are too high or too low, especially cholesterol levels, can cause long-term problems. The risk to develop atherosclerosis and coronary artery or carotid artery disease (and thus the risk of having a heart attack or stroke) increases with the total cholesterol level increasing. Nevertheless, extremely low cholesterol levels may not be healthy. Examples of disorders of lipid metabolism are hyperlipidemia (abnormally high levels of fats (cholesterol, triglycerides, or both) in the blood, may be caused by family history of hyperlipidemia, obesity, a high-fat diet, lack of exercise, moderate to high alcohol consumption, cigarette smoking, poorly controlled diabetes, and an underactive thyroid gland), hereditary hyperlipidemias (type I hyperlipoproteinemia (familial hyperchylomicronemia), type II hyperlipoproteinemia (familial hypercholesterolemia), type III hyperlipoproteinemia, type IV hyperlipoproteinemia, or type V hyperlipoproteinemia), hypolipoproteinemia, lipidoses (caused by abnormalities in the enzymes that metabolize fats), Gaucher's disease, Niemann-Pick disease, Fabry's disease, Wolman's disease, cerebrotendinous xanthomatosis, sitosterolemia, Refsum's disease, or Tay-Sachs disease.
Kidney disorders may lead to hyper or hypotension. Examples for kidney problems possibly leading to hypertension are renal artery stenosis, pyelonephritis, glomerulonephritis, kidney tumors, polycistic kidney disease, injury to the kidney, or radiation therapy affecting the kidney. Excessive urination may lead to hypotension.
Musculo-skeletal Disorders
Human serine/threonine kinase is highly expressed in the following muscle/skeleton tissues: skeletal muscle. The expression in skeletal muscle demonstrates that human serine/threonine kinase protein or mRNA can be used to diagnose diseases of the musculo-skeletal system. In addition, the activity of human serine/threonine kinase can be modulated to treat those diseases.
Components of the musculoskeletal system are skeleton, muscles, tendons, ligaments, and other components of joints. Disorders of the musculoskeletal system often cause chronic pain and physical disability. These disorders include injuries, infections, inflammation, and other types of disorders. Examples of musculoskeletal disorders include osteoporosis, postmenopausal osteoporosis, senile osteoporosis, secondary osteoporosis, idiopathic juvenile osteoporosis, Paget's disease of the bone, osteochondromas (osteocartilaginous exostoses), tumors of the bone (benign chondromas, chondroblastomas, chondromyxoid fibromas, osteoid osteomas, giant cell tumors of the bone, multiple myeloma, osteosarcoma (osteogenic sarcoma), fibrosarcomas and malignant fibrous histiocytomas, chondrosarcomas, Ewing's tumor (Ewing's sarcoma), malignant lymphoma of bone (reticulum cell sarcoma, metastatic tumors of the bone), osteoarthritis, and gout and Pseudogout.
Disorders of the joints and connective tissue include rheumatoid arthritis, psoriatic arthritis, discoid lupus erythematosus, systemic lupus erythematosus, scleroderma (systemic sclerosis), Sjögren's syndrome, connective tissue disease, polymyositis and dermatomyositis, relapsing polychondritis, vasculitis, polyarteritis nodosa, polymyalgia rheumatica, temporal arteritis, Wegener's granulomatosis, Reiter's syndrome, Behçet's syndrome, ankylosing spondylitis, or Charcot's joints (neuropathic joint disease).
Bone and joint infections include osteomyelitis and infectious arthritis.
Disorders of the muscles, bursae, and tendons include spasmodic torticollis, fibromyalgia syndromes (myofascial pain syndromes, fibromyositis), bursitis, tendinitis and tenosynovitis.
Foot problems include, for example, ankle sprain, foot fractures, heel spurs, Sever's disease, posterior Achilles tendon bursitis, anterior Achilles tendon bursitis, posterior tibial neuralgia, pain in the ball of the foot (caused by damage to the nerves between the toes or to the joints between the toes and foot), onychomycosis, and nail discoloration.
Respiratory Disorders
Human serine/threonine kinase is highly expressed in the following tissues of the respiratory system: fetal lung fibroblast IMR-90 cells, lung, lung COPD. Expression in the above-mentioned tissues and in particular the differential expression between diseased tissue and healthy tissue demonstrates that human serine/threonine kinase protein or mRNA can be used to diagnose respiratory diseases. In addition, the activity of human serine/threonine kinase can be modulated to treat those diseases.
Asthma
Allergy is a complex process in which environmental antigens induce clinically adverse reactions. The inducing antigens, called allergens, typically elicit a specific IgE response and, although in most cases the allergens themselves have little or no intrinsic toxicity, they induce pathology when the IgE response in turn elicits an IgE-dependent or T cell-dependent hypersensitivity reaction. Hypersensitivity reactions can be local or systemic and typically occur within minutes of allergen exposure in individuals who have previously been sensitized to an allergen. The hypersensitivity reaction of allergy develops when the allergen is recognized by IgE antibodies bound to specific receptors on the surface of effector cells, such as mast cells, basophils, or eosinophils, which causes the activation of the effector cells and the release of mediators that produce the acute signs and symptoms of the reactions. Allergic diseases include asthma, allergic rhinitis (hay fever), atopic dermatitis, and anaphylaxis.
Asthma is thought to arise as a result of interactions between multiple genetic and environmental factors and is characterized by three major features: 1) intermittent and reversible airway obstruction caused by bronchoconstriction, increased mucus production, and thickening of the walls of the airways that leads to a narrowing of the airways, 2) airway hyperresponsiveness caused by a decreased control of airway caliber, and 3) airway inflammation. Certain cells are critical to the inflammatory reaction of asthma and they include T cells and antigen presenting cells, B cells that produce IgE, and mast cells, basophils, eosinophils, and other cells that bind IgE. These effector cells accumulate at the site of allergic reaction in the airways and release toxic products that contribute to the acute pathology and eventually to the tissue destruction related to the disorder. Other resident cells, such as smooth muscle cells, lung epithelial cells, mucus-producing cells, and nerve cells may also be abnormal in individuals with asthma and may contribute to the pathology. While the airway obstruction of asthma, presenting clinically as an intermittent wheeze and shortness of breath, is generally the most pressing symptom of the disease requiring immediate treatment, the inflammation and tissue destruction associated with the disease can lead to irreversible changes that eventually make asthma a chronic disabling disorder requiring long-term management.
Despite recent important advances in our understanding of the pathophysiology of asthma, the disease appears to be increasing in prevalence and severity (Gergen and Weiss, Am. Rev. Respir. Dis. 146, 823–24, 1992). It is estimated that 30–40% of the population suffer with atopic allergy, and 15% of children and 5% of adults in the population suffer from asthma (Gergen and Weiss, 1992). Thus, an enormous burden is placed on our health care resources. However, both diagnosis and treatment of asthma are difficult. The severity of lung tissue inflammation is not easy to measure and the symptoms of the disease are often indistinguishable from those of respiratory infections, chronic respiratory inflammatory disorders, allergic rhinitis, or other respiratory disorders. Often, the inciting allergen cannot be determined, making removal of the causative environmental agent difficult. Current pharmacological treatments suffer their own set of disadvantages. Commonly used therapeutic agents, such as beta agonists, can act as symptom relievers to transiently improve pulmonary function, but do not affect the underlying inflammation. Agents that can reduce the underlying inflammation, such as anti-inflammatory steroids, can have major drawbacks that range from immunosuppression to bone loss (Goodman and Gilman's THE PHRAMACOLOGIC BASIS OF THERAPEUTICS, Seventh Edition, MacMillan Publishing Company, NY, USA, 1985). In addition, many of the present therapies, such as inhaled corticosteroids, are short-lasting, inconvenient to use, and must be used often on a regular basis, in some cases for life; making failure of patients to comply with the treatment a major problem and thereby reducing their effectiveness as a treatment.
Because of the problems associated with conventional therapies, alternative treatment strategies have been evaluated. Glycophorin A (Chu and Sharom, Cell. Immunol. 145, 223–39, 1992), cyclosporin (Alexander et al., Lancet 33P, 324–28, 1992), and a nonapeptide fragment of IL-2 (Zav'yalov et al., Immunol. Lett. 31, 285–88, 1992) all inhibit interleukin-2 dependent T lymphocyte proliferation; however, they are known to have many other effects. For example, cyclosporin is used as a immuno-suppressant after organ transplantation. While these agents may represent alternatives to steroids in the treatment of asthmatics, they inhibit interleukin-2 dependent T lymphocyte proliferation and potentially critical immune functions associated with homeostasis. Other treatments that block the release or activity of mediators of bronchochonstriction, such as cromones or anti-leukotrienes, have recently been introduced for the treatment of mild asthma, but they are expensive and not effective in all patients and it is unclear whether they have any effect on the chronic changes associated with asthmatic inflammation. What is needed in the art is the identification of a treatment that can act in pathways critical to the development of asthma_that both blocks the episodic attacks of the disorder and preferentially dampens the hyperactive allergic immune response without immunocompromising the patient.
COPD
Chronic obstructive pulmonary (or airways) disease (COPD) is a condition defined physiologically as airflow obstruction that generally results from a mixture of emphysema and peripheral airway obstruction due to chronic bronchitis (Senior & Shapiro, Pulmonary Diseases and Disorders, 3d ed., New York, McGraw-Hill, 1998, pp. 659–681, 1998; Barnes, Chest 117, 10S–14S, 2000). Emphysema is characterized by destruction of alveolar walls leading to abnormal enlargement of the air spaces of the lung. Chronic bronchitis is defined clinically as the presence of chronic productive cough for three months in each of two successive years. In COPD, airflow obstruction is usually progressive and is only partially reversible. By far the most important risk factor for development of COPD is cigarette smoking, although the disease does occur in non-smokers.
Chronic inflammation of the airways is a key pathological feature of COPD (Senior & Shapiro, 1998). The inflammatory cell population comprises increased numbers of macrophages, neutrophils, and CD8+ lymphocytes. Inhaled irritants, such as cigarette smoke, activate macrophages which are resident in the respiratory tract, as well as epithelial cells leading to release of chemokines (e.g., interleukin-8) and other chemotactic factors. These chemotactic factors act to increase the neutrophil/monocyte trafficking from the blood into the lung tissue and airways. Neutrophils and monocytes recruited into the airways can release a variety of potentially damaging mediators such as proteolytic enzymes and reactive oxygen species. Matrix degradation and emphysema, along with airway wall thickening, surfactant dysfunction, and mucus hypersecretion, all are potential sequelae of this inflammatory response that lead to impaired airflow and gas exchange.
Protein Kinases. Protein kinases are signal transducing enzymes that phosphorylate proteins, including other kinases, and, along with protein phosphatases, regulate the level and extent of protein phosphorylation and activation. Intracellular signalling pathways have important roles in inflammatory processes. These pathways may be activated by cytokines, oxidant stress and other inflammatory mediators (reviewed in Kyraikis and Avruch, 1996 and 2001). For example, the pro-inflammatory cytokines, tumor necrosis factor α (TNFα) and interleukin-1 activate the protein ser/thr kinases c-Jun-NH2-terminal kinase (JNK) and p38 mitogen-activated protein (MAP) kinase, leading to activation of AP-1 and IKB kinase (IKK), which, in turn, leads to activation of the transcription factor NFKB. Activation of NFKB is required for the transcription of several pro-inflammatory molecules, including interleukin-8 and ICAM-1. Enzymes of the MAP kinase class may also act to increase cytokine production by stabilization of mRNA (Winzen et al., 1999).
Inhibition of specific protein kinases has been shown to elicit anti-inflammatory effects. For example, the accumulation of polymorphonuclear leukocytes in murine lung following intratracheal administration of bacterial lipopolysaccharide can be blocked by inhibition of p38 MAP kinase (Nick, et al. 2000). As a further example, aerosol delivery to rat lungs of antisense oligodeoxynucleotides to syk kinase mRNA, suppressed nitric oxide and TNFα production from alveolar macrophages stimulated with IgG-anti-IgG complexes (Stenton et al. 2000). Protein kinase subtypes are therefore attractive therapeutic targets for the attenuation of the inflammatory response in COPD. See Kyriakis, J. M. and Avruch J. Sounding the alarm: protein kinase cascades activated by stress and inflammation. J Biol Chem 1996, 271:24313–6; Kyriakis, J. M. and Avruch, J. Mammalian mitogen-activated protein kinase signal transduction pathways activated by stress and inflammation. J. Physiol. Rev. 2001, 81:807–69; Winzen, R, Kracht, M., Ritter, B., Wilhelm, A., Chen C. A., Shyu, A., Müller, M., Gaestel, M., Resch, K., and Holtmann, H. The p38 MAP kinase pathway signals for cytokine-induced mRNA stabilization via MAP kinase-activated protein kinase 2 and an AU-rich region-targeted mechanism. EMBO J 1999, 18: 4969–4980; Nick, J. A., Young, S. Y, Brown, K. K., Avdi, N. J., Arndt, P. G., Suratt, B. T., Janes, M. S., Henson, P. M., Worthen, G. S. Role of p38 mitogen-activated protein kinase in a murine model of pulmonary inflammation. J Immunol. 2000, 164:2151–9; and Stenton, G. R., Kim, M. K., Nohara, O., Chen, C. F., Hirji, N., Wills, F. L., Gilchrist, M., Hwang, P. H., Park, J. G., Finlay, W., Jones, R. L., Befus, A. D., Schreiber, A. D. Aerosolized Syk antisense suppresses Syk expression, mediator release from macrophages, and pulmonary inflammation. J Immunol 2000, 164:3790–7.
Inflammatory Disorders
Human serine/threonine kinase is highly expressed in the following tissues of the immune system and tissues responsive to components of the immune system as well as in the following tissues responsive to mediators of inflammation: lung COPD. Expression in the above-mentioned tissues and in particular the differential expression between diseased tissue and healthy tissue demonstrates that human serine/threonine kinase protein or mRNA can be used to diagnose inflammatory diseases. In addition, the activity of human serine/threonine kinase can be modulated to treat inflammatory diseases.
Inflammatory diseases include diseases triggered by cellular or non-cellular mediators of the immune system or tissues causing the inflammation of body tissues and subsequently producing an acute or chronic inflammatory condition. Examples of such inflammatory diseases are hypersensitivity reactions of type I–IV, e.g. hypersensitivity diseases of the lung including asthma, atopic diseases, allergic rhinitis or conjunctivitis, angioedema of the lids, hereditary angioedema, antireceptor hypersensitivity reactions and autoimmune diseases, Hashimoto's thyroiditis, systemic lupus erythematosus, Goodpasture's syndrome, pemphigus, myasthenia gravis, Grave's and Raynaud's disease, type B insulin-resistant diabetes, rheumatoid arthritis, psoriasis, Crohn's disease, scleroderma, mixed connective tissue disease, polymyositis, sarcoidosis, glomerulonephritis, acute or chronic host versus graft reactions.
Genitourinary Disorders
Human serine/threonine kinase is highly expressed in the following urological tissues: fetal kidney, kidney, kidney tumor. Expression in the above-mentioned tissues and in particular the differential expression between diseased tissue and healthy tissue demonstrates that human serine/threonine kinase protein or mRNA can be used to diagnose urological disorders. In addition, the activity of human serine/threonine kinase can be modulated to treat genitourological disorders.
Genitourological disorders comprise benign and malign disorders of the organs constituting the genitourological system of female and male, renal diseases such as acute or chronic renal failure, immunologically mediated renal diseases such as renal transplant rejection, lupus nephritis, immune complex renal diseases, glomerulopathies, nephritis, toxic nephropathy, obstructive uropathies such as benign prostatic hyperplasia (BPH), neurogenic bladder syndrome, urinary incontinence such as urge-, stress-, or overflow incontinence, pelvic pain, and erectile dysfunction.
Benign Prostatic Hyperplasia. Benign prostatic hyperplasia (BPH) is the benign nodular hyperplasia of the periurethral prostate gland commonly seen in men over the age of 50. The overgrowth occurs in the central area of the prostate called the transition zone, which wraps around the urethra BPH causes variable degrees of bladder outlet obstruction, resulting in progressive lower urinary tract syndromes (LUTS) characterized by urinary frequency, urgency, and nocturia due to incomplete emptying and rapid refilling of the bladder. The actual cause of BPH is unknown but may involve age-related alterations in balance of steroidal sex hormones.
Selective α1-adrenoceptor antagonists, such as prazosin, indoramin, and tamsulosin, are used as an adjunct in the symptomatic treatment of urinary obstruction caused by BPH, although they do not affect on the underlying cause of BPH. In BPH, increased sympathetic tone exacerbates the degree of obstruction of the urethra through contraction of prostatic and urethral smooth muscle. These compounds inhibit sympathetic activity, thereby relaxing the smooth muscle of the urinary tract. Uroselective α1-antagonists and α1-antagonists with high tissue selectivity for lower urinary tract smooth muscle that do not provoke hypotensive side-effects should be developed for the treatment.
Drugs blocking dihydrotestosterone have been used to reduce the size of the prostate. 5α-reductase inhibitors such as finasteride are prescribed for BPH. These agents selectively inhibit 5α-reductase which mediates conversion of testosterone to dihydrotestosterone, thereby reducing plasma dihydrotestosterone levels and, thus, prostate growth. The 5α-reductase inhibitors do not bind to androgen receptors and do not affect testosterone levels, nor do they possess feminizing side-effects.
Androgen receptor antagonists are used for the treatment of prostatic hyperplasia due to excessive action or production of testosterone. Various antiandrogens are under investigation for BPH including chlormadione derivatives with no estrogenic activity, orally-active aromatase inhibitors, and luteinizing hormone-releasing hormone (LHRH) analogues.
Urinary Incontinence. Urinary incontinence (UI) is the involuntary loss of urine. Urge urinary incontinence (UUI) is one of the most common types of UI together with stress urinary incontinence (SUI), which is usually caused by a defect in the urethral closure mechanism. UUI is often associated with neurological disorders or diseases causing neuronal damage, such as dementia, Parkinson's disease, multiple sclerosis, stroke, and diabetes, although it also occurs in individuals with no such disorders. One of the usual causes of UUI is overactive bladder (OAB), which is a medical condition referring to the symptoms of frequency and urgency derived from abnormal contractions and instability of the detrusor muscle.
There are several medications for urinary incontinence on the market today, mainly to help treating UUI. Therapy for OAB is focused on drugs that affect peripheral neural control mechanisms or those that act directly on bladder detrusor smooth muscle contraction, with a major emphasis on development of anticholinergic agents. These agents can inhibit the parasympathetic nerves, which control bladder voiding, or can exert a direct spasmolytic effect on the detrusor muscle of the bladder. This results in a decrease in intravesicular pressure, an increase in capacity, and a reduction in the frequency of bladder contraction. Orally active anticholinergic drugs, such as propantheline (ProBanthine), tolterodine tartrate (Detrol), and oxybutynin (Ditropan), are the most commonly prescribed drugs. However, their most serious drawbacks are unacceptable side effects, such as dry mouth, abnormal visions, constipation, and central nervous system disturbances. These side effects lead to poor compliance. Dry mouth symptoms alone are responsible for a 70% non-compliance rate with oxybutynin. The inadequacies of present therapies highlight the need for novel, efficacious, safe, orally available drugs that have fewer side effects.
Serine/Threonine Kinases and Treatment of Urological Disorders
Serine/Threonine kinases, such as protein kinase C (PKC) and myosin light-chain kinase (MLCK) are known to play physiological roles in urination through controlling the contraction of bladder smooth muscles.
PKC is a serine/threonine kinase, which consists of at least 10 isoforms. The isoforms have distinct features in structure, substrate requirement, expression profiles, and intracellular localization. Five PKC isoforms (β1, β2, δ, ε, and ζ) are expressed in rat dorsal root ganglion (DRG). When cultured DRG neurons were stimulated by Bradykinin (BK), only PKCε specifically translocates to the plasma membranes, indicating a physiological importance of PKCε in neuronal response in rat DRG. Cesare, et al., Neuron 23, 617–24, 1999. PKCε is abundantly expressed in the central and peripheral nerve systems. It is activated by diacylglycerol or TPA in an independent manner of Ca2+, which is different from classical PKCs. Nishizuka, Science 258, 607–14, 1992; Way et al., Trends in Pharm. Sci. 21, 181–87, 2000.
Recent studies showed that BK-evoked thermal hypersensitivity was attenuated in vanilloid receptor 1 (VR1) knockout mice. Julius et al., Nature 413, 203–10, 2001. Furthermore, BK markedly enhanced proton- and capsaicin-evoked membrane potentials in VR1/B2-transfected cells. These results imply that BK is involved in overactive bladder and urinary incontinence through the VR1-mediated sensory nerve potentiation, because VR1 plays a key role in the sensory C-fiber afferent nerves. Desensitization by VR1 agonists such as capsaicin and resiniferatoxin is currently being evaluated in clinical study for the treatment of urinary incontinence. Chuang et al., Nature 411, 957–62, 2001.
Thus, it appears that activation of PKC-epsilon plays a pivotal role in the BK-evoked VR1-mediated sensitization of sensory nerves in hyperactive bladder. Therefore, PKCε inhibitors may have therapeutic potential for the treatment of overactive bladder and urinary incontinence.
Bladder filling and emptying is well-balanced coordinated control of contraction and relaxation of the bladder body, the bladder base and urethra. Contraction of smooth muscle is produced by the sliding of actin filaments against myosin filaments. The head regions of myosin molecules attach to adjacent actin filaments in an ATP-dependent manner. One of the two light chains on the head regions of the myosin-II molecule is phosphorylated during muscle contraction. When this light chain is phosphorylated, the myosin head interacts with an actin filament and causes contraction, whereas the myosin head dissociates from actin when the light chain is dephosphorylated. The phosphorylation is catalyzed by MLCK, which requires the binding of a Ca2+/calmodulin complex for activation. Therefore, the contractile state of bladder smooth muscle is mediated by Ca2+-regulated phosphorylation of myosin light chains in the assembly units.
A high degree of insertion of 7-amino acids near the ATP-binding region and LC20 phosphorylation in myosin from the bladder body samples was demonstrated, although non-inserted myosin and the low level of myosin light chain phosphorylation was observed in the urethra. Prior studies have shown that the inserted myosin has a two-fold higher actin-activated ATPase activity compared to the insert-less isoform. The tight contraction of bladder dome may help to facilitate rapid force development and emptying, while loose contraction may contribute to slowly or non-cycling myosin cross bridges and the maintenance of a tonic or contracted state during bladder filling. Hypolite et al., Scand. J. Urol. Nephrol. (Suppl. 201), 46–50, 1999.
This invention further pertains to the use of novel agents identified by the screening assays described above. Accordingly, it is within the scope of this invention to use a test compound identified as described herein in an appropriate animal model. For example, an agent identified as described herein (e.g., a modulating agent, an antisense nucleic acid molecule, a specific antibody, ribozyme, or a human serine/threonine kinase polypeptide binding molecule) can be used in an animal model to determine the efficacy, toxicity, or side effects of treatment with such an agent. Alternatively, an agent identified as described herein can bemused in an animal model to determine the mechanism of action of such an agent. Furthermore, this invention pertains to uses of novel agents identified by the above-described screening assays for treatments as described herein.
A reagent which affects serine/threonine kinase activity can be administered to a human cell, either in vitro or in vivo, to reduce serine/threonine kinase activity. The reagent preferably binds to an expression product of a human serine/threonine kinase gene. If the expression product is a protein, the reagent is preferably an antibody. For treatment of human cells ex vivo, an antibody can be added to a preparation of stem cells that have been removed from the body. The cells can then be replaced in the same or another human body, with or without clonal propagation, as is known in the art.
In one embodiment, the reagent is delivered using a liposome. Preferably, the liposome is stable in the animal into which it has been administered for at least about 30 minutes, more preferably for at least about 1 hour, and even more preferably for at least about 24 hours. A liposome comprises a lipid composition that is capable of targeting a reagent, particularly a polynucleotide, to a particular site in an animal, such as a human. Preferably, the lipid composition of the liposome is capable of targeting to a specific organ of an animal, such as the lung, liver, spleen, heart brain, lymph nodes, and skin.
A liposome useful in the present invention comprises a lipid composition that is capable of fusing with the plasma membrane of the targeted cell to deliver its contents to the cell. Preferably, the transfection efficiency of a liposome is about 0.5 μg of DNA per 16 nmole of liposome delivered to about 106 cells, more preferably about 1.0 μg of DNA per 16 nmole of liposome delivered to about 106 cells, and even more preferably about 2.0 μg of DNA per 16 nmol of liposome delivered to about 106 cells. Preferably, a liposome is between about 100 and 500 nm, more preferably between about 150 and 450 nm, and even more preferably between about 200 and 400 nm in diameter.
Suitable liposomes for use in the present invention include those liposomes standardly used in, for example, gene delivery methods known to those of skill in the art. More preferred liposomes include liposomes having a polycationic lipid composition and/or liposomes having a cholesterol backbone conjugated to polyethylene glycol. Optionally, a liposome comprises a compound capable of targeting the liposome to a particular cell type, such as a cell-specific ligand exposed on the outer surface of the liposome.
Complexing a liposome with a reagent such as an antisense oligonucleotide or ribozyme can be achieved using methods that are standard in the art (see, for example, U.S. Pat. No. 5,705,151). Preferably, from about 0.1 μg to about 10 μg of polynucleotide is combined with about 8 nmol of liposomes, more preferably from about 0.5 μg to about 5 μg of polynucleotides are combined with about 8 nmol liposomes, and even more preferably about 1.0 μg of polynucleotides is combined with about 8 nmol liposomes.
In another embodiment, antibodies can be delivered to specific tissues in vivo using receptor-mediated targeted delivery. Receptor-mediated DNA delivery techniques are taught in, for example, Findeis et al. Trends in Biotechnol. 11, 202–05 (1993); Chiou et al., GENE THERAPEUTICS: METHODS AND APPLICATIONS OF DIRECT GENE TRANSFER (J. A. Wolff, ed.) (1994); Wu & Wu, J. Biol. Chem. 263, 621–24 (1988); Wu et al., J. Biol. Chem. 269, 542–46 (1994); Zenke et al., Proc. Natl. Acad. Sci. U.S.A. 87, 3655–59 (1990); Wu et al., J. Biol. Chem. 266, 338–42 (1991).
Determination of a Therapeutically Effective Dose
The determination of a therapeutically effective dose is well within the capability of those skilled in the art. A therapeutically effective dose refers to that amount of active ingredient that increases or decreases enzymatic activity relative to the enzymatic activity which occurs in the absence of the therapeutically effective dose.
For any compound, the therapeutically effective dose can be estimated initially either in cell culture assays or in animal models, usually mice, rabbits, dogs, or pigs. The animal model also can be used to determine the appropriate concentration range and route of administration. Such information can then be used to determine useful doses and routes for administration in humans.
Therapeutic efficacy and toxicity, e.g., ED50 (the dose therapeutically effective in 50% of the population) and LD50 (the dose lethal to 50% of the population), can be determined by standard pharmaceutical procedures in cell cultures or experimental animals. The dose ratio of toxic to therapeutic effects is the therapeutic index, and it can be expressed as the ratio, LD50/ED50.
Pharmaceutical compositions that exhibit large therapeutic indices are preferred. The data obtained from cell culture assays and animal studies is used in formulating a range of dosage for human use. The dosage contained in such compositions is preferably within a range of circulating concentrations that include the ED50 with little or no toxicity. The dosage varies within this range depending upon the dosage form employed, sensitivity of the patient, and the route of administration.
The exact dosage will be determined by the practitioner, in light of factors related to the subject that requires treatment. Dosage and administration are adjusted to provide sufficient levels of the active ingredient or to maintain the desired effect. Factors that can be taken into account include the severity of the disease state, general health of the subject, age, weight, and gender of the subject, diet, time and frequency of administration, drug combination(s), reaction sensitivities, and tolerance/response to therapy. Long-acting pharmaceutical compositions can be administered every 3 to 4 days, every week, or once every two weeks depending on the half-life and clearance rate of the particular formulation.
Normal dosage amounts can vary from 0.1 to 100,000 micrograms, up to a total dose of about 1 g, depending upon the route of administration. Guidance as to particular dosages and methods of delivery is provided in the literature and generally available to practitioners in the art. Those skilled in the art will employ different formulations for nucleotides than for proteins or their inhibitors. Similarly, delivery of polynucleotides or polypeptides will be specific to particular cells, conditions, locations, etc.
If the reagent is a single-chain antibody, polynucleotides encoding the antibody can be constructed and introduced into a cell either ex vivo or in vivo using well-established techniques including, but not limited to, transferrin-polycation-mediated DNA transfer, transfection with naked or encapsulated nucleic acids, liposome-mediated cellular fusion, intracellular transportation of DNA-coated latex beads, protoplast fusion, viral infection, electroporation, “gene gun,” and DEAE- or calcium phosphate-mediated transfection.
Effective in vivo dosages of an antibody are in the range of about 5 μg to about 50 μg/kg, about 50 μg to about 5 mg/kg, about 100 μg to about 500 μg/kg of patient body weight, and about 200 to about 250 μg/kg of patient body weight. For administration of polynucleotides encoding single-chain antibodies, effective in vivo dosages are in the range of about 100 ng to about 200 ng, 500 ng to about 50 mg, about 1 μg to about 2 mg, about 5 μg to about 500 μg, and about 20 μg to about 100 μg of DNA.
If the expression product is mRNA, the reagent is preferably an antisense oligonucleotide or a ribozyme. Polynucleotides that express antisense oligonucleotides or ribozymes can be introduced into cells by a variety of methods, as described above.
Preferably, a reagent reduces expression of a human serine/threonine kinase gene or the activity of a serine/threonine kinase polypeptide by at least about 10, preferably about 50, more preferably about 75, 90, or 100% relative to the absence of the reagent. The effectiveness of the mechanism chosen to decrease the level of expression of a human serine/threonine kinase gene or the activity of a human serine/threonine kinase polypeptide can be assessed using methods well known in the art, such as hybridization of nucleotide probes to serine/threonine kinase-specific mRNA, quantitative RT-PCR, immunologic detection of a human serine/threonine kinase polypeptide, or measurement of enzymatic activity.
In any of the embodiments described above, any of the pharmaceutical compositions of the invention can be administered in combination with other appropriate therapeutic agents. Selection of the appropriate agents for use in combination therapy can be made by one of ordinary skill in the art, according to conventional pharmaceutical principles. The combination of therapeutic agents can act synergistically to effect the treatment or prevention of the various disorders described above. Using this approach, one may be able to achieve therapeutic efficacy with lower dosages of each agent, thus reducing the potential for adverse side effects.
Any of the therapeutic methods described above can be applied to any subject in need of such therapy, including, for example, mammals such as dogs, cats, cows, horses, rabbits, monkeys, and most preferably, humans.
Diagnostic Methods
Human serine/threonine kinase also can be used in diagnostic assays for detecting diseases and abnormalities or susceptibility to diseases and abnormalities related to the presence of mutations in the nucleic acid sequences that encode the enzyme. For example, differences can be determined between the cDNA or genomic sequence encoding serine/threonine kinase in individuals afflicted with a disease and in normal individuals. If a mutation is observed in some or all of the afflicted individuals but not in normal individuals, then the mutation is likely to be the causative agent of the disease.
Sequence differences between a reference gene and a gene having mutations can be revealed by the direct DNA sequencing method. In addition, cloned DNA segments can be employed as probes to detect specific DNA segments. The sensitivity of this method is greatly enhanced when combined with PCR For example, a sequencing primer can be used with a double-stranded PCR product or a single-stranded template molecule generated by a modified PCR. The sequence determination is performed by conventional procedures using radiolabeled nucleotides or by automatic sequencing procedures using fluorescent tags.
Genetic testing based on DNA sequence differences can be carried out by detection of alteration in electrophoretic mobility of DNA fragments in gels with or without denaturing agents. Small sequence deletions and insertions can be visualized, for example, by high resolution gel electrophoresis. DNA fragments of different sequences can be distinguished on denaturing formamide gradient gels in which the mobilities of different DNA fragments are retarded in the gel at different positions according to their specific melting or partial melting temperatures (see, e.g., Myers et al., Science 230, 1242, 1985). Sequence changes at specific locations can also be 5 revealed by nuclease protection assays, such as RNase and S 1 protection or the chemical cleavage method (e.g., Cotton et al., Proc. Natl. Acad Sci. USA 85, 4397–4401, 1985). Thus, the detection of a specific DNA sequence can be performed by methods such as hybridization, RNase protection, chemical cleavage, direct DNA sequencing or the use of restriction enzymes and Southern blotting of genomic DNA. In addition to direct methods such as gel-electrophoresis and DNA sequencing, mutations can also be detected by in situ analysis.
Altered levels of serine/threonine kinase also can be detected in various tissues. Assays used to detect levels of the receptor polypeptides in a body sample, such as blood or a tissue biopsy, derived from a host are well known to those of skill in the art and include radioimmunoassays, competitive binding assays, Western blot analysis, and ELISA assays.
All patents and patent applications cited in this disclosure are expressly incorporated herein by reference. The above disclosure generally describes the present invention. A more complete understanding can be obtained by reference to the following specific examples, which are provided for purposes of illustration only and are not intended to limit the scope of the invention.